Boss Ideas 8 didn't quite turn out how I'd hoped, as it ended up being entirely composed of human bosses and like 2 worms. Therefore, I have forbidden myself to make any actual human bosses for now (at least in this group).

Not much has really changed, though certain aspects have returned from previous versions, such as some of the debuffs like Heavy Gravity, Crimson Embers, Chaotic Ember, etc.



However! There is a new 'gimmick' for this set of bosses: EX Variants.

EX Variants are mainly just recoloured variants of certain bosses. Originally, they were going to have more major design changes, but as these are basically just statistically-superior versions of the original bosses and that most people aren't going out of their way to face them, the additional work would just slow things down for what is basically technically just the same amount of bosses.

Not every boss will have an EX variant, however. Usually, if a boss already have a stronger variant faced later an EX would be deemed unnecessary and thus isn't created. The stronger version MAY have an EX, but it isn't guaranteed either.

(Also, I mean, Kirby does it and nobody complains so it shouldn't be too big of an issue :P)

Appearance: A large Stick Insect-like creature with an Ivy Chest for a head; lined with teeth made from the metal joints of the chest. Its body is literally made of sticks, with leaves protruding from many of the joints and a fan of leaves for a tail.

Summon: Found within a sealed room near the Jungle Temple under the main room. Opening it with a 2nd Temple Key allows the player to interact with a chest in the centre of the room. Right-clicking the chest will cause it to disappear, with the Mimic appearing in its place. After a couple of seconds it will become active and begin attacking. Despawns if the player dies or moves too far away, with the chest disguise respawning for when the player returns.

Fought: Hardmode
Specification: Post-Plantera
Special: No Summoning Item
Progression: No

Stats:
Health: 45,000 (70,000)
Attack:
-55 (100) (Melee)
-40 (74) (Spike Traps, Flamethrower)
-45 (82) (Bombs)
Defence: 13

Attacks:
Will often follow a cycle of running at the player, jumping 3 times, and then using one of its three special attacks. Repeats the cycle again afterwards.
-It may release numerous spike traps from its mouth that linger on the floor for a while, like Spiked Balls; dealing contact damage until they eventually despawn.
-It may spew a stream of fire from its mouth at the player, with similar range to the Flamethrower. [In Expert Mode it also releases a bouncing fireball]
-It may release numerous bombs at varying arcs that act similar to Grenades; bouncing or rolling before eventually exploding; dealing AoE damage.
Its movement speed and attack speed will gradually increase as its health depletes, but does so faster in Expert Mode.

Defeat: Explodes into gibs and leaves an actual Ivy Chest of loot in the nearest location to itself that it can. The "Chest" can respawn later.

Drops: All placed inside the chest. May include a sword, flail, magic tome, bow, special grenade-like ranged weapon, or a summoner staff that summons Mimics as minions. In Expert Mode it will also drop the Trusting Mimic; a mount that when used will place the player inside of a mimic: reducing movement to short-hops and jumps but majorly increases defence.

Hints:
-Make some platforms. These both give the player a way of dodging its charges (as they are entirely ground-restricted) and can make its grenades less threatening as they'll just fall through
--Though, bear in mind, the spikes do not ignore the platforms. Also, its jumps can fall through platforms if necessary; like with King Slime.
-Don't bother trying to fight it within its chamber, as the room provided is slightly smaller than the Golem's room; nowhere near big enough for such a fast-moving boss

Extra Info:
-The boss is, quite literally, a 'stick-insect' due to being made of sticks.
--It was also compared to Hollow Knight's Nosk due to its deceptive nature, unnaturally slender body, and fast movements.
-Originally, it was intended to have a Dungeon counterpart with a Dungeon Chest for a head and a bulkier body. However, as the Dungeon's chests are just Gold Chests, the fact there would need to be 3 variants for the three types, and the Dungeon's generation rarely making a suitably-sized room, this idea was scrapped.
[Added: 18/12/19]

Appearance: The Ivy Mimic's EX form. Its leaves take on a more golden appearance, the metal from the chest becomes more saturated and the wood across its whole body darkens and appears more reddish in colour.

Summon: Use the Radiant Chest anywhere in the world. The boss will despawn if the player moves too far away or dies, like with most bosses.
Throughout the entire fight all players are inflicted with the Heavy Gravity debuff, reducing vertical flight speed by 75%.

Fought: Hardmode
Specification: Post-Ivy Mimic
Special: EX Boss
Progression: No

Stats:
Health: 65,750 (115,000)
Attack:
-75 (140) (Melee)
-66 (118) (Spike Traps, Flamethrower, Fireball)
-70 (127) (Bombs, Shockwave)
Defence: 18

Attacks:
Essentially a harder variant of the Ivy Mimic; using a similar, though buffed, attack pattern. It still runs at the player, jumps, and then uses one of its 3 attacks, though the running is faster, jumps higher, and the attacks themselves deadlier:
-The Spike Traps are larger and remain hazardous for an extended period of time
-More Bombs are launched with the bomb attack, and there are now 3 types; regular, bouncy, and sticky. They act the same as their grenade counterparts.
-The Flamethrower has more range and fireballs are continuously released randomly from the stream. Mimic can also slowly walk towards the player.
Once down to 50% health it gains an additional ability. After landing from the final jump it can create a shockwave, similar to the Ogre's, upon landing for the 3rd time.

Defeat: Explodes into gibs, like before. As it isn't an 'overworld interaction' there are no fake chests to respawn, so nothing special happens.

Drops:
Will drop the Mimic's Spirit 100% of the time as its only Normal-mode drop. In Expert it will additionally drop the Lure Spirit. Both of these items are essentially decoration on their own, but act as potential materials later-on.

Hints:
-As the superior version of the original Ivy Mimic, all of its stats and attacks have been buffed. Some Expert-exclusive things like the fireballs have become part of the basic attack, and it even gained a whole new ability not seen at all in the original fight.
-Being airborne is a good way to dodge its ramming attack and 'special attacks', but leaves you quite vulnerable to its jumps. Dashes are also great for dodging the jumps and special attacks also, but itself leaves you open to the ramming attack.
--Combining the two; dashing whilst airborne, makes it a lot easier to dodge the boss' attacks with proper understanding of its attack cycle.

Extra Info:
-Originally, this was the boss that would have been the Dungeon Mimic. However, for the reasons stated prior, this never occurred.
[Added: 18/12/19]

Appearance: The WYRM's base form; a large mechanical worm coated in a dark grey shell. It has two small 'teeth' prodtruding from the front of its face. Little of the actual worm within is visible, though of what is seen it appears to be purple and pink.

Summon: Use the Armour-Beta anywhere in the world. The boss will despawn if the player dies, but will chase a player across the world if they try to flee; often increasing in speed drastically if the player gets too far away.

Fought: Pre-Hardmode
Specification: Post-Skeletron
Special?: No
Progression: Later Bosses

Stats:
Health: 20,000 (38,750)
Attack:
-60 (100) (Head Melee)
-30 (52) (Body Melee)
-25 (40) (Laser)
Defence: 10

Attacks:
Acts like a fairly basic worm boss, burrowing through the ground to attack the player.
-It will fire lasers at the player occasionally. The lasers are actually quite slow, but have a very minor homing effect on the player for the first few seconds it is active. [In Expert Mode the homing effect lasts longer and the projectiles are faster]
As its health wanes, the frequency of its laser fire will gradually increase. [The fire rate starts off faster in Expert Mode, and also increases faster as well.]

Defeat: Will explode into fiery gibs upon defeat. The explosion doesn't hurt the player.

Drops:
Metal Plating is dropped in large quantities, used to craft weapons and armour. Will additionally drop Beta Energy Cells, also used in these recipes and in a few other ones later-on. In Expert Mode it will drop more of these Platings and Cells, but also drops a bow that can be upgraded later on.

Hints:
-A high-up platform or remaining airborne with additional jumps make dodging its contact damage, the most dangerous part of the boss, a lot easier to avoid.
--As the player cannot really get any good wings at this point, they aren't as viable of an option as they would otherwise be later on in the game

Extra Info:
-The 'Beta Wyrm' was originally the 'Alpha', though was changed as a one of this group of bosses was removed.
-This boss is the first of a 'trio' of worm bosses, apparently all the same worm in different armour, fought throughout the game.
[Added: 19/12/19]

Appearance: A large dragon coated in sharp copper scales. It has red claws and a large ring of copper spikes surrounding its tail. Its underbelly and eyes are a light orange colour.

Summon: Use the Copper Seal anywhere in the world. The boss will despawn if the player dies or moves too far away, though the further away the player gets the faster the boss will move, meaning that the only way to despawn it without dying would be teleporting across a large portion of the map so it can't gain the move speed boosts necessary to catch the player again.

Fought: Post-Moon Lord
Specification: Post-Moon Lord
Special: No
Progression: Later Bosses

Stats:
Health: 355,000 (500,000)
Attack:
-130 (210) (Melee)
-110 (176) (Fireball, Bouncing Fire, Flame Breath)
-100 (160) (Embers, Flame Wisps)
-115 (182) (Flame Rockets, Eruption Traps)
-200 (450) (Flame Burst)
Defence:
-140 +70% Damage Resistance (Phase 1)
-120 +45% Damage Resistance (Phase 2)
-100 +20% Damage Resistance (Phase 3)

[All attacks excluding Melee will inflict Dragon Flame - A debuff that deals 15 Damage per Second]

Attacks:
Phase 1:
Will charge at the player 3 times and then use a fire attack, with each charge covering a lot of ground but having a reasonable amount of time between charges. It has access to a few of its attacks at this point.
-May flap its wings, summoning a multitude of fireballs to rain down from the sky diagonally. The direction they fall from is based on what side of the boss the player is standing as it prepares to summon them.
-May fly at the player, breathing flame breath at them. The breath will also release lingering wisps of flame that deal minor damage.
-May release numerous bouncing fireballs in random directions around itself. Around 8-10 [9-12] fireballs will be released at once. The fireballs, upon hitting any solid blocks, leave lingering embers where they hit that deal minor damage.
In this phase, it has a large amount of defence and thus the phase transition happens at only 85% health into its 2nd phase. The transition is signalled by the Drake roaring, with many of its scales falling from its body afterwards.
Phase 2:
The player is inflicted with Heavy Gravity, restricting vertical flight by 75%. Its charges are as fast as before, and the same amount occur before it uses a fire attack.
It retains all of its phase 1 attacks, but also gains new ones as well:
-It may launch numerous 'flame rockets' from its mouth in a similar manner to the Mourning Wood's 'Flaming Wood' attack. However, the Drake's are faster, pass through blocks and inflict a debuff
-It may create numerous wisps of fire at random locations nearby. After a few seconds they 'explode', creating large balls of flame that linger in-place, obstructing the player's movement.
At 50% health, the Drake will transition to its 3rd phase, also signalled by it letting out a bellowing roar and shedding scales.
Phase 3:
The Heavy Gravity debuff is removed from the player. It charges 5 times before attacking, and whilst all the charges don't cover as much ground they are faster and the time between charges is reduced significantly.
It retains its previous fire attacks, but gains a single new addition as well:
-Its last new attack, the Flame Burst, has it launch a massive fireball at the player. The fireball passes through blocks and deals a massive amount of damage, plus it can be used alongside other attacks within a single attack cycle. However, it is slow and very easy to spot once unleashed due to its size and the light it produces.

Defeat: Lets out a distressed roar and a massive amount of scales fall from its body. It will fall out of the sky, but instead of acting as 'gibs' it will instead just fall down into the background, ignoring blocks (thus causing it to just fall off-screen very quickly).

Drops:
Will drop a large quantity of Copper Scales; materials for a fairly large amount of items. Also drops a gun that launches explosive spikes, a magic staff that summons fireballs, a sword that releases a fiery explosion on hit and a summoning staff that summons a mini Copperplated Drake as a minion. In Expert Mode it has 2 additional drops. The guaranteed drop is the Sharpened Scale, which increases damage and armour piercing, and the rare drop is a Copper Egg; that summons a baby Copperplated Drake as a pet (smaller than the minion, so they aren't the same).

Hints:
-Have some platforms prepared for the 2nd phase of the fight, as the reduced flight height means that dodging its charges becomes considerably harder, even despite their predictability.
-Use high-damage weapons for the first phase. Many attacks, especially ones will low damage due to their effects, may be reduced to a single point of damage in this phase.
-The 3rd phase's fast pace means that charges and teleports may be recommended
-Don't stay too close to the boss, as this simply just provides more problems than benefits. It makes the charges harder to dodge, makes contact damage more likely, makes dodging attacks like the flame breath harder, and also makes dodging its most powerful attack harder due to the reduced time to respond.
-The flame burst attack, despite its damage, is really easy to avoid; especially at night where it lets off a powerful glow.

Extra Info:
-Originally, this was planned to be the Unbreakable Drake, a far more intimidating and powerful boss. However, due to the boss not looking anything like the Unbreakable Drake by the time the sprite was mostly done, it became a different boss entirely.
--Someday... Unbreakable Drake... someday...
-Ironically enough Copper, arguably Terraria's worst ore, is used to make one of the most resilient and powerful bosses on this page.
[Added: 19/12/19]

Appearance: The EX version of the Copperplated Drake. Its spikes are made of a shiny obsidian and its underbelly and wings appear to have lava within them due to the fiery orange colours.

Summon: Use the Radiant Seal anywhere in the world. The despawning mechanics are the same as the Copperplate Drake; meaning the player would either have to die or teleport far enough away to get the boss to despawn.

Fought: Post-Moon Lord
Specification: Post-Copperplated Drake
Special: EX Boss
Progression: No

Stats:
Health: 485,000 (700,000)
Attack:
-200 (333) (Melee)
-165 (261) (Fireball, Bouncing Fire, Flame Breath)
-155 (242) (Embers, Flame Wisps)
-188 (300) (Flame Rockets, Eruption Traps)
-300 (550) (Flame Burst, Flame Aura)
Defence:
-150 +70% Damage Resistance (Phase 1)
-126 +45% Damage Resistance (Phase 2)
-102 +20% Damage Resistance (Phase 3)

[All attacks excluding Melee will inflict Dragon Flame - A debuff that deals 15 Damage per Second]

Attacks:
Phase 1:
Mostly similar to the Copperplated Drake's attacks, though beefed-up. Will charge 4 times at the player before attacking, with the time between charges being slightly less than the Copperplate's.
-The fireballs are more numerous, meaning the space between them is reduced significantly.
-The flame breath has increased range, and more wisps are created during the flame breath. The wisps also linger for a longer time.
-The fireball attack's fireballs last longer, bounce and move faster, and create embers that linger longer.
The phase transition is similar to with the Copperplate; with the Drake roaring and shedding scales. Still happens at 85% health.
Phase 2:
Heavy Gravity is inflicted at the start of this phase, as before. The charges speed up slightly compared to its first phase.
It retains all of its previous attacks, though gains its new phase 2 ones and an additional new attack exclusive to the Obsidian Drake:
-The flame rockets are larger, faster, and more numerous. They also have a very slight homing effect for the first second they are active.
-The Eruption Traps create larger fireballs, and the fireballs continuously release embers whilst active. The embers fall to the ground.
-Its new attack has the Drake fly close to the player, and then create an explosion of flame around itself that deals massive damage.
At 48% health it will transition into its 3rd phase; slightly later than its non-EX counterpart
Phase 3:
Heavy Gravity debuff is removed, and the boss now charges 5 times rapidly before using one of its fire attacks. The charges are extremely fast, cover a lot of ground, and there is little time between each charge.
-Flame Burst is faster, but nothing else changes for that attack.
However, now it has the ability to combine two attacks with a single attack cycle. For the Copperplate, this was originally just for the Flame Burst, but now it can apply to virtually any of the Drake's attacks.

Defeat: Virtually the same as the Copperplate's; where it loses a lot of scales and falls from the sky.

Drops:
Always drops the Drake's Spirit as its only Normal-mode drop. It additionally drops the Obsidian Spirit in Expert Mode. As with the Mimic, both of these items are decorative until they are all collected.

Hints:
-This fight is mainly just a buffed-up version of the Copperplated Drake, so practice makes perfect here as well.
--Though, do be aware that the fight still has more than just statistical changes, as it gains a new attack and all of its previous attacks are buffed in varying ways.
-Keep your distance. I am aware that this was one of the points for the Copperplate as well, but in this version it is even more important as its new attack is short-ranged and all of its attacks deal excessive damage, even for an early Post-Moon Lord boss

Extra Info:
-The exact shades of obsidian used are the same as the reflective obsidian dye; a touch very similar to the Copperplate using the reflective copper dye for its colour scheme.
-It was at one point going to have a special drop called the Obsidian Scale. However, as EX Bosses do not get their own set of unique drops, it was instead given to the regular variant as the 'copper scale' accessory instead.
[Added: 19/12/19]

Appearance: A further-enhanced version of the WYRM Beta fought previously. Its segments are larger and spikier, and the 2 small fangs at the front of the Beta are now a lot larger and have a pair of smaller ones just outside of them.

Summon: Use the Armour-Delta; an upgraded version of the Armour-Beta made by adding Beta Energy Cells and hardmode materials such as souls and a Lihzahrd Power Cell. The boss only despawns if the player dies, and will chase them across the map if they try to flee.

Fought: Hardmode
Specification: Post-Golem (Also Post-WYRM Beta)
Special: No
Progression: Later Bosses

Stats:
Health:
-100,000 (176,500) (WYRM)
-150 (255) (Drone)
Attack:
-150 (255) (Head Melee)
-80 (140) (Body Melee, Sawblades)
-110 (188) (Tracking Field) (Inflicts Electrified - 100%)
-65 (108) (Lasers) (Inflicts On Fire! - 50 [100]%)
Defence:
-30 (WYRM)
--+40% Damage Resistance (Per Segments Pierced, Mulitplicative)
-20 (Drone)

Attacks:
The Wyrm burrows, as with most early-game worm bosses. It frequently launches its projectile attacks at the player.
-It may launch a barrage of lasers at the player from all of its segments. While they are numerous, they cannot pierce blocks so any buried segments of the boss will not be able to fire lasers at the player. Additionally, they have lost their homing capabilities the Beta Wyrm had.
-It may launch a cluster of Sawblades out from its head. These are fired in random directions and at random speeds around itself, but will all rapidly slow down; eventually lingering in-place where they stop for a long time. The sawblades can block and deflect the player's projectiles, though they remain friendly to the player [except in Expert Mode, where they become hazardous to the player once deflected].
-It may launch a small cluster of small projectiles from its head that form a 'net'. The net follows the player at a reasonably fast place, gradually getting smaller. Once it gets small enough it will explode, damaging the player heavily if they were unable to escape it.
At varying percentages of health or other special conditions it will perform certain special abilities separate from its main attack cycles:
-If it deems the player 'unreachable' it will be granted temporary flight until the player gets close enough to the ground again.
-For every 10% of its health lost will cause it to summon a group of 4-7 (8) probes, that fly near the player whilst firing lasers at them; much like the Destroyer's
-Once down to 33 [50]% health the player will be inflicted with the Heavy Gravity debuff, which lasts until the end of the fight

Defeat: Explodes into fiery gibs. Like with the Beta, the explosion doesn't damage the player.

Drops:
Reinforced Plating is dropped in large quantities, which is used to craft armour and weapons in late Hardmode and the early Post-Moon Lord game. Also drops Delta Energy Cells, used for a few recipes of their own as well. In Expert Mode more of these are dropped, but it can also drop the Delta Stream; used to upgrade the bow dropped by the Beta Wyrm.

Hints:
-Piercing weapons are less effective the more segments they travel through, likely being reduced to very minor damage by the 2nd, 3rd or 4th segment, which reduce damage by 64%, 78.4%, and 87.04% respectively.
-High-up platforms are less effective for just cheesing the boss, but are very helpful for when it inflicts Heavy Gravity on the player, as dodging it with just wings alone would become exceptionally hard to do.
-If it uses the Tracking Field's 'net' keep moving away from it, as it deals high damage once it activates the explosion
--Dashing or teleporting away just before it explodes can also work

Extra Info:
-The Delta Wyrm was originally the Beta Wyrm until one of the 4 Wyrms was removed, where the names were changed.
[Added: 20/12/19]

Appearance: Terminus looks very similar to how he used to, though has swapped his scarf for a cape. The golds on his robes are now a lot more reflective. However, ultimately, it's still Terminus.

Summon: Found on the beach at the same side of the world as the Jungle, though never spawns in the water itself. Can be interacted with like Town NPCs, and selecting 'challenge' will allow the place to face Terminus.
The first bit of dialogue he will always say is "You seem... surprised to see me..."

Fought: Hardmode
Specification: Post-Golem
Special: No Summoning Item, Interactable NPC
Progression: Later Bosses

Stats:
Health: 95,000 (155,750)
Attack:
-100 (160) (Melee)
-85 (134) (Crimson Flares, Crimson Maw)
-115 (186) (Red Phantoms, Ground Spikes)
-65 (100) (Shadowflame Embers) (Inflicts Shadowflame - 50 [100]%)
-70 (108) (Ichorian Pulse) (Inflicts Ichor - 100%)
-N/A (200) (Chaos Dustcutter)
Defence: 20

(All of Terminus' attacks inflict Crimson Embers - 33 [50]%, which deals 12 damage per second and increases damage vulnerability by 10%)

Attacks:
Phase 1:
Terminus will move near the player, attack, and move again. His movements act similar to teleports, but have after-images travelling to the place he is moving to, and he is vulnerable whilst moving. He has a large array of attacks based on some of his old fights:
-He may appear either horizontally to the player and dash at them in a straight line. The dash is very fast, but is locked to only moving along the x-axis.
--Similarly, he may appear above the player and dash downward at them, which is also similarly locked along the y-axis to compensate for its fast speed.
-He may swipe the air in front of him, summoning a large amount of Crimson Flares. They all move outward at varying speeds, decelerating as they do so. Once they stop they explode.
-He may launch a flurry of Red Phantom projectiles at the player. They are fast and deal high damage, but cannot pass through blocks nor deviate from their path at all; which is faced towards the player's location when the attack was used.
Once taken down to 50 [65]% health he will say "You still fight with urgency, just like before." before transitioning to his 2nd phase, additionally signalled by a pulse of red energy.
Phase 2:
Terminus will now teleport to move, meaning he cannot be attacked whilst repositioning. Much like the Lunatic Cultist, he will still leave his after-images in the direction he moves, so it's still fairly easy to track him.
-Terminus may launch 4-5 [5] 'bursts' of flares outward in random directions. The first 2 bursts have 7 fireballs, the 3rd and 4th 8, and the 5th will have 9.
-Terminus may dash downward and strike the ground, causing large red spikes to burst from the ground in random locations. The places they emerge from are signalled by red particles. The attack is only used when the player is near the ground.
-Terminus may launch Shadowflame Fireballs skyward, before they begin to rain down from the sky over a period of a few seconds.
-Terminus may move near the player and release a pulse of golden energy, called the Ichorian Pulse. It will inflict the player with Ichor for a long time if hit.
-He may unleash a massive barrage of Crimson Maw projectiles at the player. Their angles are slightly randomised as opposed to all being aimed directly at the player.
[Once taken down to 30% health Terminus will say "Your spirit is unmistakable." before releasing another pulse of red energy and transitioning to his 3rd phase.]
Phase 3: [Expert-Exclusive]
Terminus will draw a rapier-esque sword called the Chaos Dustcutter to replace his two dash attacks from Phase 1. His teleports no longer leave after-images, so tracking his movements is harder. Additionally, Crimson Maws will now stop after travelling for around a second and re-adjust their trajectory towards the player again; essentially 'dashing' at the player.
-Terminus' last new attack is a string of chain-dashes with the Dustcutter. After the 3rd and final dash he will launch 3 Crimson Maws at the player in an arc.

Defeat: Falls back to the ground, bows, and disappears with another pulse of red energy as seen in his phase transitions.

Drops:
Drops a sword, chain-knife flail, tome, magic staff, summoning staff, sentry staff, bow or gun. Will drop Chaotic Fragments; used for a few summoning items and some vanity accessories. In Expert Mode he will additionally drop the Phantasmal Cloak; an accessory that boosts movement speed, attack speed, dodge changes, and defence. May, very rarely, drop the Chaos Dustcutter as well; an extremely powerful weapon that is still good in Post-Moon Lord.

Hints:
-Dashes and teleports are, as ever, extremely helpful for this fast-paced boss.
-As most of its attacks are variations or direct ports of 2 of its fights from Boss Ideas 7, some idea of those bosses may be helpful for this one as well.
-If in Expert Mode, get used to both of his dash attacks. The beefed-up Dustcutter versions can potentially 3-shot the player from full health due to their extremely high damage.

Extra Info:
-Considering that Terminus was believed to have been slain at the end of Boss Ideas 7's semi-final-boss, seeing him alive and well might be a bit surprising
--This is the reason for his dialogue when first interacting with him.
--However, as in Boss Ideas 7 Terminus survived apparent disintegration and a violent beatdown from 2 other powerful entities and the player, seeing him survive against all odds a 3rd time shouldn't be too much of a shock
-He seems to recognise the player, likely because of Boss Ideas 7, even saying that their 'spirit' is the same (in case of fighting him with a different character from 7, which would likely be the case.
[Added: 21/12/19]

Appearance: The WYRM's final form; with larger bulkier segments and more spikes. Its jaws have been extended further and have a 3rd set of smaller ones just inside of the largest set.

Summon: Use the Armour-Omega; the final upgrade of the Armour-Beta made using the Armour-Delta and some Post-Moon Lord materials and some lunar fragments and Luminite. The boss will only despawn if the player dies; chasing them across the map if they flee.
The player is also inflicted with the Heavy Gravity debuff throughout the entire fight.

Fought: Post-Moon Lord
Specification: Post-Moon Lord
Special: No
Progression: Later Bosses

Stats:
Health:
-1,000,000 (1,675,000) (WYRM)
-1,000 (1,750) (Drone)
Attack:
-200 (385) (Head Melee)
-120 (205) (Body Melee, Sawblades, Electro-Ball)
-150 (260) (Tracking Field) (Inflicts Electrified - 100%)
-100 (178) (Lasers, Probe Melee) (Inflicts On Fire! - 100%)
-0.2x (0.4x) (Deflected Projectiles' Damage)
Defence:
-45 (WYRM)
--+65% Damage Resistance (Per Segment Pierced, Multiplicative)
-80 (Drone)

Attacks:
As with its previous incarnations, it burrows; made more dangerous by the player's limited vertical movement. Its burrowing speed is incredibly fast; reaching around 200 mph whilst the player is nearby and 500 mph if pursuing the player across the map. It retains its projectile attacks, but they are more dangerous than before.
-It may fire a barrage of lasers at the player from all of its segments. Unlike before, these ones can pass through blocks, but the barrage only lasts a few seconds.
-It may launch clusters of sawblades outward randomly from both its head and the nearest segment of its body to the player. The sawblades, as before, decelerate and become stationary. They deflect the player's projectiles, making them hostile regardless of difficulty.
-It may cause all of its segments to simultaneously drop sawblades at their current locations. They act like the other sawblades, which means attacking the segments with piercing weapons will trigger their deflecting abilities.
-The 'Tracking Field' is now spawned from the segment closest to the player. The field's movement is now faster, allowing it to 'lock-on' to the player easier. It explodes once small enough regardless of where the player is, as before.
-It may summon a large orb of electricity that chases the player slowly, periodically firing lasers at the player before it despawns.
Like before, if certain conditions are met it will gain special abilities:
-If the player is too far away, it will both gain its speed boost and a flight ability to allow it to chase the player easier.
-For every 5% health lost it will summon 4-5 [5-7] probes from its body that chase the player, firing lasers at them.

Defeat: Explodes into fiery gibs. The explosions, unlike before, will deal it's body segments' contact damage if the player is too close.

Drops:
Enduring Plating is dropped in large quantities, plus Omega Energy Cells: both used to craft Post-Moon Lord items. In Expert Mode it drops the Omega Current; used to upgrade the bow dropped by the Beta Wyrm for the final time.

Hints:
-The restrictions to flight make this boss' contact damage even more dangerous. Dashes, dodges, teleports, and any other methods good for dodging should be used if possible.
-Keep moving during its laser barrage either clockwise or anti-clockwise around its body. As it targets the player's position with each subsequent laser if you don't keep moving or if you try to change directions you'll probably get hit.
-Dashing or teleporting free of the Tracking Field is, as before, a good way of avoiding it.
-The boss' immense speed means dodging the head's melee damage is very difficult. Keep an eye of what it's doing, or you're likely to receive a sudden chunk of damage.

Extra Info:
-Unlike the other two, this one was already planned to be called the 'Omega', as the original 'Delta' was the one that was scrapped.
-The boss is, technically, one of the fastest-moving bosses in the game outside of bosses who have access to teleportation mechanics, like Terminus and the Moon Lord.
[Added: 21/12/19]

Appearance: An enhanced version of the WYRM Omega. Its silvery armour has been replaced with a shiny gold, and what is visible of its body is purple and blue as opposed to its original magenta and purple.

Summon: Use the Radiant Armour, made using the Armour-Omega and some of the Omega's drops. It can be summoned anywhere and only despawns once the player dies; chasing them across the world if they try to flee.
The player is inflicted with Heavy Gravity throughout the entire fight.

Fought: Post-Moon Lord
Specification: Post-WYRM Omega
Special: EX Boss
Progression: No

Stats:
Health:
-1,500,000 (2,650,000) (WYRM)
-1,500 (2,875) (Drone)
Attack:
-340 (500) (Head Melee)
-180 (342) (Body Melee, Sawblades, Electro-Ball)
-220 (400) (Tracking Field) (Inflicts Electrified - 100%)
-140 (285) (Lasers, Probe Melee) (Inflicts On Fire! - 100%)
-0.4x (0.6x) (Deflected Projectiles' Damage)
Defence:
-60 (WYRM)
--+75% Damage Resistance (Per Segment Pierced, Multiplicative)
-100 (Drone)

Attacks:
Its movements are the same, and its attacks are essentially just buffed-up versions of the Omega's attacks.
-Its laser barrage has more lasers and lasts roughly a second longer.
-Its sawblade 'bursts' are summoned from the 3 segments closest to the player, as well as its head still
-All of its segments may still drop sawblades, as before, as this attack hasn't changed.
-The tracking field is a lot faster, making it very hard to escape it.
-The electric orb will travel faster and fires lasers more frequently at the player
The boss will also still speed up and begin flying if the player is too far away or out of reach, and still summons drones in groups of 7 [10] for every 5% of its health lost.

Defeat: As before, it will explode into fiery gibs. The explosions still damage the player.

Drops:
Will drop the Armoured Spirit in Normal Mode as its only drop. In Expert Mode, it will additionally drop the Burrower's Spirit. Both are mainly for vanity purposes, but have a single recipe if enough are gathered.

Hints:
-Most of the points from the Omega still work here, as it is virtually just an enhanced version of the Omega's fight
-The field's increased speed means the player would likely need to continue moving away from it to avoid being hit, or dashing or teleporting once it prepares to explode. However, do make sure not to move too far from the boss of it might cause it to pursue the player.

Extra Info:
-As the Omega was the Wyrm's most powerful form, it was the only one to receive an EX version of itself.
-Surprisingly, unlike the other EX bosses seen up to this point, the Wyrm doesn't receive any new attacks; just buffs to the ones the Omega had.
[Added: 21/12/19]

Appearance: Terminus, though he has swapped his red cloak for a light blue hooded one. Additionally, he has seemingly gained a new scarf that similarly flows in the wind.

Summon: Find Terminus at the beach, and talk to him. The player must have the Radiant Spirit in their inventory, and if they do a 3rd option will appear in Terminus' menu other than Chat and Challenge, called 'Chaos?'. Selecting this will cause Terminus to give new dialogue.
"Chaos? I gave up with that a long time ago now."
"But, I have still been putting my talents towards... something..."
"A... redemption... I suppose"
Terminus will then transform, and the fight will begin very shortly.

Fought: Chaos Mode
Specification: Post-Shade
Special: EX Boss (Technically), Secret Boss, No Summoning Item
Progression: No

Stats:
Health: 9,750,000 (15,875,000)
Attack:
-520 (700) (Melee)
-560 (760) (Chaos Dustcutter)
-502 (674) (Red Phantoms, Ground Spikes, Crimson Ring)
-500 (671) (Crimson Flares, Crimson Maw)
-480 (650) (Ichorian Pulse) (Inflicts Ichor - 100%, Inflicts Cursed Flames - 100%)
-400 (552) (Shadowflame Embers) (Inflicts Shadowflame - 100%)
-0 (10) (Pulse) (Inflicts 2 [3] Random Debuffs - 100%)
-850 (2000) (Execution)
Defence: 100

(All of Terminus' attacks inflict Crimson Embers - 100%)

Attacks:
Phase 1:
Terminus will use all of its attacks from its previous fight, across all of its 3 phases before. It uses its teleportation mechanic from Terminus' 2nd phase; teleporting but leaving after-images that move in the direction which it travels.
Once down to 55 [60]% health, it will transition to its 2nd phase, signalled by a burst of light and more dialogue: "Maybe I'll spice things up a bit'
Phase 2:
Terminus moves the same, but the after images are fewer so tracking his teleports is a little harder. He gains new attacks that he uses alongside his previous attacks:
-He may release a pulse of energy that will inflict 2 [3] random debuffs on any nearby players. The debuffs only last a few seconds, but almost any can be chosen. The range of the pulse is roughly 30 blocks in all directions, and due to the speed of the pulse it is almost impossible to dodge without being far enough away prior.
-He may summon two Crimson Rings, large red glowing rings, and throw them. One is thrown at the player and acts like a Boomerang, while the other is thrown diagonally downward and bounces like a Flower of Fire fireball. The 'Boomerang' one is then thrown at the player again once it returns to Terminus, though doesn't return to him a 2nd time.
-He may summon a ring of 8 Crimson Maws around himself, then teleport elsewhere and do it again. This may happen up to 3 [5] times in succession before switching to a new attack.
-He may launch numerous crimson flares diagonally into the sky. After a couple of seconds they will begin flying-in horizontally from the side they were originally launched towards.
In this phase Terminus' attacking speed will increase and the time between his teleports will decrease the lower his health gets.
-He may lift his sword skyward and the screen may darken. After a couple of seconds he will dash a short distance toward the player and slash. The dash only covers around 5 blocks but the slash, called the 'Execution', deals immense damage.

Defeat: Falls to the ground, then disappears in a small burst of light.

Drops:
Radiant Essence; a material used to make a lot of late-game items, as well as a Spirit Cloak; both an accessory and a material. In Expert Mode it will additionally drop the Crimson Staff; which can summon 'Images' of Terminus to attack enemies.

Hints:
-Knowledge of Terminus' original fight is strongly recommended, as his first phase is essentially just a beefed-up version of that fight.
--Also, bear in mind that he retains the Dustcutter, something that in his original fight was restricted to Expert Mode, in his Normal-Mode Apothesis fight as well
-Staying fairly close to solid ground, preferably an arena made of semisolid platforms, as his Phase 2 pulse can inflict Petrified; which can instantly kill the player if far enough from the ground.
-If you suspect he is trying to use the 'Execution' attack, signalled by the screen darkening, do not try and approach Terminus for any reason. The Execution is more than capable of 1-shotting the player in Expert, and in Normal will still likely take away the majority of the player's health.
-The Ankh shield may be able to negate some of the debuffs inflicted by the pulse.

Extra Info:
-The fight was inspired by an unused fight back from Boss Ideas 7 of the same name. While the original fight had a sprite made, it wasn't used because "it looked bad."
-- The original sprite is a little buggy due to the animation speed messing up, but this is what remains of it.
-Technically, this fight is able to inflict the most debuffs of almost any boss, due to its pulse being able to pick almost any set of debuffs it wants.
-The Pulse technically inflicts 3 [4] debuffs when factoring in that it will always inflict Crimson Embers
--Technically, if it rolls Crimson Embers with both [all 3] of its rolls, it will only inflict a single debuff
---Additionally, certain effects that stack (e.g. Webbed + Frozen) or ones with inferior effects (e.g. Frozen vs Slowed/Chilled) will technically make one of the debuffs virtually worthless. This is most common with immobilising debuffs paired with other immobilising debuffs or speed-reducing ones, but can also apply for things like Withered Weapon and Cursed; as Cursed would prevent use of your weapon regardless.
[Added: 22/12/19]

Appearance: A purple metallic machine with grey 'spikes' over its body; most around two large glass-like orbs; one at the top of its body and one at the bottom. A stream of 'electricity' travels between two of the spikes at its base.

Summon: Use the Suspicious-Looking Remote at the surface or space. While the boss doesn't despawn if taken underground, it cannot be summoned there. The boss despawns if the player dies or moves too far away.

Fought: Pre-Hardmode
Specification: Post-EoW
Special: No
Progression: No

Stats:
Health:
-2,450 (3,880) (Tech)
-300 (450) (Drones)
Attack:
-22 (35) (Melee)
-20 (31) (Lasers, Drone Melee, Sparks)
-32 (50) (Missiles)
Defence:
-10 (Tech)
-7 (Drones)

Attacks:
The Tech flies around above the player, attacking the player with lasers and missiles.
-The lasers are fired downward from the orb at its base. The Tech will try to fly directly overhead whilst doing this, and will fire roughly 10 lasers.
-It may release sparks from the large orb on its top. The sparks are affected by gravity and disappear on contact with blocks.
-It may launch missiles at the player. The missiles move slow but will home-in on the player for roughly 5 seconds before losing its homing capabilities. The missiles explode on contact with the player or blocks.
At 50% [Both 66% and 33%] health it will become invulnerable and summon 3 mini versions of itself, called drones, that orbit it. The drones need to be destroyed to continue attacking the main boss.

Defeat: Explodes into fiery gibs. The explosion doesn't deal damage.

Drops:
A boomerang, magic staff, or a bow. Drops a lot of Meteorite, as well as Space Scrap; used as a material to craft some items. In Expert Mode it may drop a sword that can launch red-hot laser projectiles when swung.

Hints:
-If firing its lasers downward the player can simply keep moving horizontally in 1 direction and it will never be able to hit you.
-Having a few layers of platforms can make dodging the missile attack easier, as simply using one or two levels of platform might make it hard to dodge.

Extra Info:
-The boss is quite easy considering how early in the game it is, though its homing attack might cause a problem
[Added: 21/12/19]

Appearance: Alien Tech's EX Variant. Its main body retains the same colours, though they have been darkened and given a more blueish tint. The glassy 'domes' on its body have all been replaced by light blue ones, and the same goes for the stream of electricity at its base.

Summon: Use the Radiant Remote at the surface or in space. The boss will only despawn if the player flees or dies, unaffected by location and time despite its spawning mechanics.

Fought: Pre-Hardmode
Specification: Post-Alien Tech
Special: EX Boss
Progression: No

Stats:
Health:
-3,350 (5,800) (Tech)
-400 (700) (Drones)
Attack:
-30 (50) (Melee)
-26 (45) (Lasers, Drone Melee, Sparks) (Inflicts Electrified - 33 [50]%)
-45 (70) (Missiles) (Inflicts On Fire! - 50 [100]%)
Defence:
-12 (Tech)
-10 (Drones)

Attacks:
Moves and attacks in a similar manner to the original fight, though its attacks have been buffed considerably to make it more of a threat.
-The original laser attack has been replaced by a laser barrage. While still fired downward the angles of the lasers are random, and a lot of lasers will be fired in only a few seconds.
-The sparks fall faster and after the first burst is released a 2nd burst of sparks will follow suit.
-The missiles are a bit faster, plus they also retain their homing capabilities for 7 seconds as opposed to 5.
At 60% and 10% [At 75%, 50% and 25%] it will summon its 3 drones. While they still orbit the main body, and while the main body is still invulnerable and capable of attack, the new addition is that the drones themselves can now attack the player. Roughly every 1.5 seconds [every second] they will fire a single laser at the player each. The time is reduced very slightly if 1 drone is defeated, and halved if only 1 remains. Destroying all 3 drones makes the main boss vulnerable again so the fight can properly continue.

Defeat: Explodes into fiery gibs. The explosion doesn't hurt the player.

Drops:
Will drop the Circuit Spirit in Normal Mode, and in Expert Mode drops the Alien Spirit; both mainly used for vanity until enough are collected.

Hints:
-This fight is ultimately a LOT tougher than the original, and is more comparable to an early Hardmode fight than one that can be faced before Skeletron. Therefore, proper knowledge of the original fight is good for at least some base understanding of how the fight pans out.
-A total of 5,750 (12,100) health must be got through, so the fight may take a while. Therefore, bring some spare potions along in case you need to re-apply any buffs.
-It is suggested to fight this boss somewhere in late Pre-Hardmode or early Hardmode, as its health and potential damage output are very high for something Pre-Hardmode.

Extra Info:
-Originally, this boss was intended to use the Martian Madness colour scheme as a parallel to the original using the Meteor colours. However, this was scrapped because it didn't look as good.
--Hence why the boss has the ability to inflict Electrified; a debuff which in Vanilla Terraria can only be inflicted by enemies from the Martian Madness event
-The Stormtech has some of the most drastic changes of any EX Boss, with changes to all of its attacks, Expert-Mode implementations in Normal Mode, and (technically) a colossal health boost (if including the drones, which MUST be destroyed to progress the fight).
[Added: 22/12/19]

Appearance: A large draconic wolf with blue fur. While most of its body simply just appears to be a larger-than-average wolf, it also has a large set of wings on its back which it can use for flight, even if temporary.

Summon: Use the Ice Fang in the snow biome. Using the item will summon a blizzard that lasts throughout the fight. Wolves and Werewolves have an increased spawn rate throughout the fight also. Leaving the snow biome for an extended time, getting too far from the boss, or dying will cause it to despawn. If the player goes too high they will be given a debuff called Frigid Cold; immediately negating any remaining flight time and reducing vertical flight by around 50% until the debuff expires.

Fought: Hardmode
Specification: Post-Mechanicals
Special: No
Progression: No

Stats:
Health: 20,000 (32,500)
Attack:
-60 (110) (Melee)
-50 (89) (Hail)
Defence: 16

Attacks:
The Wolfdrake will run around, running and lunging at the player in a manner similar to Wolves. However, it will jump to try and match the player's height, and if needs be ignore solid blocks to reach the player. It still has a few other attacks at its disposal:
-It may let out a roar, causing large chunks of ice to begin falling from the sky for a few seconds. More pieces of ice fall if the boss is at low health [and even more in Expert Mode].
-It may jump into the air, open its wings, and charge at the player up to 3 times in succession. After finishing the charges it will become grounded again.
-It may let out a roar, summoning in anywhere from 2-8 [4-8] Wolves. These wolves do not have any special properties, but unlike other boss summons there isn't a cap on how many can be spawned aside from the sprite limit.

Defeat: Lets out a yelp, falls to the ground, shakes off some snow and runs/flies away. Any Wolves nearby will instantly lose aggression towards the player, but Werewolves will not.

Drops:
Ice-themed weapons such as a sword, spear, and a magic tome. Additionally drops Dragon Pelt; used for a range of items including a set of armour. In Expert Mode it will additionally drop the Hunter's Bow; a material actually used to craft an accessory or an actual working bow.

Hints:
-While staying airborne will make it easier to dodge the Wolves and the boss' fast running, the player must make sure not to go too high as to avoid being debuffed and thus being forced back onto the ground for a time.
-AoE and piercing weapons are very useful for dealing with the Wolves spawned throughout the boss, as it is likely that they will be able to quickly flood the screen if the Wolfdrake summons them a couple of times.
-Dashes are good for dodging the charges
-As the player's visibility will be obstructed partially from the blizzard, it may be harder to see the hail chunks falling. Therefore, the player will have to watch what the Wolfdrake is doing and, if they see it howl and no new Wolves spawn, they know to watch the sky for movement.
-Ice Golems may spawn. Just a heads-up.

Extra Info:
-The Hunter's Bow is said to have apparently belonged to a legendary warrior. However, as of present, no such warrior is known.
--However, being an important part of an Expert Boss' drop's tooltip, it will likely have some importance later-on.
[Added: 23/12/19]

Appearance: The Wolfdrake's EX counterpart. The main difference between this one and its regular version is that its blue fur is now a dark grey, though little else is too noticeably different.

Summon: Use the Radiant Fang in the snow biome. A blizzard begins that remains throughout the fight. Wolves and Werewolves' spawn rates are increased throughout the fight rather drastically. Leaving the snow biome will now enrage the boss instead of despawning it, doubling its damage and defence and making it attack faster, though dying or fleeing far enough will still cause it to despawn. Frigid Cold is still inflicted if the player flies too high.

Fought: Hardmode
Specification: Post-Wolfdrake
Special: EX Boss
Progression: No

Stats:
Health: 28,950 (44,250)
Attack:
-90 (165) (Melee)
-75 (130) (Hail)
Defence: 20

Attacks:
The Wild Dragon moves faster and jumps higher, as well as gaining an additional double-jump if unable to reach the player in 1 jump, but cannot change direction for the 2nd jump.
-It may roar and cause chunks of hail to fall from the sky. The hail pieces are larger and certain pieces will be spiked; with spikes pieces planting themselves in blocks on contact and lingering for a few seconds before despawning.
-Its charges are faster and cover more ground. It still charges 3 times before ending the attack, with the 3rd charge covering more ground than the previous 2.
-It may roar and summon anywhere from 5-10 [8-10] Wolves.
-It may roar; releasing a shockwave of blue energy from its mouth. The player is briefly inflicted with Frigid Cold regardless of distance, mainly just to cancel the player's remaining flight time due to how little time it lasts. This is the Wild Dragon's only new attack.

Defeat: As before, it will yelp and fall to the ground. Only a second or so later it gets up, shakes the snow off its pelt, and flees. Wolves do not lose their aggression unlike normal.

Drops:
In Normal Mode it will drop the Wolf Spirit and in Expert Mode it additionally drops the Wild Spirit. Both of these items are vanity until enough spirits have been collected.

Hints:
-The fight is a lot faster-paced than the original, so dashes are almost required in order to reliably avoid being hit.
-Layers of platforms in this fight are both useful and a hindrance. On one hand they can help quickly reset the Frigid Cold debuff the Wild Dragon can inflict, but also having them can give the Dragon vertical movement options, which is dangerous considering it already has some of the best horizontal movement.
-Piercing and AoE attacks are still good for dealing with the Wolves spawned, which is even more helpful as even more Wolves spawn in this fight

Extra Info:
-So far this is the only EX boss to have a biome requirement to fight it. However, unlike the original fight, it will enrage instead of despawning like its regular counterpart.
[Added: 23/12/19]

Appearance: A chaotic entity, like Terminus, dressed in a suit and top hat. While the top hat was a previous boss' signature, and that boss had ties to the chaotic entities, it doesn't appear to be him. One of his eyes appears to be covered by the hat.

Summon: Use the Chaos Heart anywhere in the world. The screen will darken and Shade will appear, with an arena of blocks (roughly 140x100) being formed around the player. Shade will usually begin with dialogue, though is invulnerable until he has finished speaking. Once finished, he will become vulnerable and begin to attack.
"...Hmm?"
"What? Did you expect someone like the Doppelganger?"
"Oh please! Those stories are over now!"
"It's my time in the spotlight!"

Fought: Post-Moon Lord
Specification: Post-Famished
Special: Activates Chaos Mode
Progression: Chaos Mode

Stats:
Health:
-2,500,000 (3,450,000) (Phase 1)
-3,000,000 (4,425,000) (Phase 2)
Attack:
-345 (520) (Phase 1 Melee, Phase 2 Hand Melee)
-325 (488) (Shade Ember)
-350 (527) (Phantasmal Sphere)
-300 (430) (Lingering Flames)
-370 (565) (Phase 2 Melee)
Defence:
-70 (Phase 1)
-100 (Phase 2)

Attacks:
Phase 1:
Will attack, teleport, and attack; following this cycle throughout the first phase. His teleports will create black clouds both from where it disappears and re-appears. He will attack between each teleport, using one of many different attacks:
-He may create a vertically-moving 'bullet-hell' of Shade Ember projectiles that rain down from the sky over a fairly long period of time, often lingering until Shade begins a new attack
-He may release a single burst of shade embers from himself in all directions. While the projectiles' positions are random, the sheer number means that almost every direction is at least partially covered.
-He may release 3 bursts of projectiles, though they only have around 20-25 [25-30] projectiles per burst. However, they are released in rather quick succession.
-He may launch a stream of shade embers at the player; continuously launching them for around 8 seconds at high speed and in very rapid succession.
-He may summon 5-7 [6-8] Phantasmal sphere projectiles around himself. After doing this, one of two things will happen:
--He may launch them all at the player, still in their ring formation.
--He may launch them at the player one at a time, though in quick succession.
-He may dash at the player, leaving a trail of flames where he moves. These flames linger for a fairly long time.
-He may dash at the player 3 times, leaving lingering flame trails based on where he moves. The dashes have slightly shorter range compared to the single-dash variant, however.
Once reduced to 0 health, he will let out a shout and disappear into a cloud of smoke. After afew seconds, he will exclaim "Do you think that you can really stop me!?" before re-appearing in a cloud of smoke in the 2nd phase with a different appearance.
Phase 2:
Shade has now changed into a skeletal being with Skeletron-esque floating hands and a potentially physics-defying 'scarf'. His health bar changes and his attacks are also different. He moves by 'dashing' to a new location, accompanied by after-images created as he moves.
-He retains the 4 Shade Ember attacks from Phase 1, though the bursts are usually fired out of his hands as opposed to the main body, and the bursts alternate between hands if more than 1 is fired during a single attack.
-The Phantasmal spheres are now summoned so that 5 orbit each hand. One hand will then launch them at the player in ring formation whilst the other 'throws' them at the player one at a time.
-It may launch Phantasmal Spheres from both its hands at the same time. Each hand will do this about 5-7 [7] times before ending the attack.
-He may swipe his hands at the player, with the swipes leaving the ember trails from his Phase 1 dash attacks. The trails are not left when retracting his hands back to the main body, however, at the attack is considered to have ended.
-He may have one of his hands fly near the player before attempting to 'crush' the player by having his hand lunge at them suddenly. The hand will return to Shade shortly after.

Defeat: Shudders, then explodes into clouds of smoke with a shout. Chaos Mode will activate if not already active in the player's world also; causing more powerful enemies and 2 new ores to spawn.

Drops:
Shade Fragments and Spirits of Chaos are his main drops; both materials for crafting a fairly large array of decently-powerful items. He may also additionally drop the Vile Pendant during rematches, and in Expert Mode the Tattered Hat; both accessories that provide special effects to the player, usually after filling a meter by either taking or dealing damage.

Hints:
-His two phases have fairly similar attacks, so knowledge on Phase 1 will still be beneficial during Phase 2.
-He has considerably high health for a boss at this point in the game, so make preparations.
-The player should take a moment to heal and re-apply buffs during the transition. Sadly, the transition to Phase 2 isn't long enough to simply fly to the ground to regenerate naturally.
-The player, even without prior knowledge on the fight, should be able to guess that Phase 1 isn't all there is to it (because Phase 2 isn't hinted at in the fight, as it has a completely different health bar and everything). The boss has very low health for his placement progression-wise, so the player should probably suspect a 2nd phase to the fight.

Extra Info:
-Shade's design looks most similar to Terminus and Omnicron; two villains who appeared in Boss Ideas 7 and 4 respectively.
--However, he is stated to not have anything to do with Omnicron, despite the top hat and all-black attire in his first phase, and his skeletal appearance in his 2nd.
-Shade seems to fill Terminus' role from Boss Ideas 7; being the gateway to Chaos Mode.
-Shade is the only Chaotic Entity seen so far not introduced in Boss Ideas 7
[Added: 22/12/19]

Appearance: Shade's EX variant. Shade seems mostly the same as his regular counterpart, though has swapped his original black suit for a white one. However, as the suit makes up most of his physical appearance, the change seems a lot more drastic.

Summon: Use the Radiant Heart anywhere in the world. The background will turn grey and the boss will spawn in, with an arena (roughly 140x100) of unbreakable blocks appearing with the player in the centre. The boss only despawns if the player dies or flees, like a lot of other bosses. Unlike his regular counterpart he doesn't have any dialogue.

Fought: Chaos Mode
Specification: Post-Shade
Special: EX Boss
Progression: No

Stats:
Health:
-3,000,000 (5,000,000) (Phase 1)
-3,450,000 (5,875,000) (Phase 2)
Attack:
-460 (640) (Phase 1 Melee, Phase 2 Hand Melee)
-425 (586) (Shade Ember)
-450 (628) (Phantasmal Sphere)
-410 (565) (Lingering Flames)
-500 (700) (Phase 2 Melee)
Defence:
-82 (Phase 1)
-120 (Phase 2)

Attacks:
Phase 1 is mostly the same as the original fight in terms of actions, though as with all EX bosses the attacks themselves have been buffed:
-The vertical bullet-hell travels faster and will always linger into roughly the first half of the following attack
-The single 'Shade Ember Burst' is now followed up almost immediately by a 2nd, smaller burst, consisting of fewer projectiles. However, the 2nd burst's projectiles accelerate as they travel.
-The 'triple-burst' attack will have Shade quickly teleport between the bursts, and each burst consists of more projectiles.
-The 'Shade Ember Stream' is mostly the same, but will last longer before Shade switches to a new attack
-The Phantasmal Sphere attacks are mostly the same, but the spheres are larger and move faster
-The flame trails from both the single and triple-dash attacks will linger for a longer time, and their surface area has increased.
The transition from Phase 1 is mostly the same, having Shade release a burst of energy before transforming. It still occurs as Shade reaches 0 health.
Phase 2:
Shade's attack patterns, as with the original fight, will change after transforming.
-He still retains the Shade Ember attacks from Phase 1, and as before they will alternate between hands if using the bursts. Additionally, the 'stream' attacks are launched from both hands simultaneously.
-The sphere attacks are the same as the original, except that they are larger and faster. Additionally, it will always go for a 'high-roll' when deciding how many spheres to summon.
-The hand swipes are the same, but the flame trails linger for an extended time.
-The 'crush' attack itself is the same, but also has a new variant where it will just 'charge' at the player from beside Shade as opposed to lingering near the player as normal.

Defeat: Shudders and explodes into a cloud of smoke with an echoing shout.

Drops:
-In Normal Mode it will always drop the Shady Spirit, and in Expert it will also drop the Malevolent Spirit: both are mainly vanity until enough of them have been gathered.

Hints:
-As this fight is essentially just a harder version of Shade's original fight, practicing the original fight will still help with this one
-Take time to re-apply buffs during the transition. Also, bear in mind that because there is no dialogue the transition period is actually shorter than the original Shade fight.

Extra Info:
-This is the only EX variant of a boss to be fought in a different 'section' of the game (Chaos Mode as opposed to Post-Moon Lord). This is because Shade is the gateway boss to Chaos Mode and, because EX Bosses can only be faced upon defeating their normal counterparts, the world would have to be in Chaos Mode to summon this boss.
-This version of Shade appears to be using the same colours as the White Tuxedo vanity set. Similarly, Shade's regular fight uses the Black Tuxedo colours.
[Added: 22/12/19]

Well, to make up for the lack of larger bosses from #8, #9 has far more large bosses. Hopefully, this'll make up for that :P

Well, as with 5 and 7, this one will consist of numerous parts across a few different pages. While there's fewer bosses per page than those two, this time it is because of the sheer number of EX bosses meaning that if I didn't, the pages would end up being too long to scroll through via the sub-menu, which defeats the entire purpose of dividing them in the first place

Discord:
https://discord.gg/URhX8GU
The Discord has a few people on it now, so feel free to join and say 'Hi' :)


[This page receives the Tomato Trending award for making it to the top of the Popular Guides page]

As usual, feel free to post ideas in the comments below or over on the Discord server. Both are fine, and I'll try to respond to any submissions if possible.

Anyways, see you next time! :)