Noticed there wasn't much info on the game and all info in game is very obscure at hinting you what the heck everything does.

I covered the most important sections of the game which impact the game and generally useful info towards unlocking all achieves.

Forging is one of main game mechanics. You input % of materials you want to use, potentially adding extra enhance materials which are reward for 'replacing' your forged items.

Forge has a mechanic which allows you to further improve or regress the item by +/-5 tiers.
In minigame you have to click the anvil on correct moments. I recommend full screen for that.

Forging initially takes 20 minigame clicks to complete but one of IMO most important 'pure ore'(boss currency) perks remove amount of clicks you need by 2 per level.
If you max out the perk at lvl 10 - you will get instant perfect crafts removing the minigame entirely.

There is also one item which slows minigame by ~25% at tier ~100 but yet again obsolete since it's better to just invest 10 pure ore per run into the above perk.

Forging quality:
Quality of item is much less important than you might think. Legendary quality item is ~5-10% stronger than poor quality when at same tier.

Legendary quality requires a fixed 4 essence per tier of item.

That being said assuming you max out the craft minigame until it's skipped - you can farm infinite essence by simply spam crafting some unit item infinitely.

This means a free ~5-10% boost with some tiny effort.

Best gems:
Gems are super fast to explain for min max reasons.
All gems you have unlocked have equal chance of appearing when crafting item.

Early on - don't bother UNLOCKING gems past earth. Earth is best one until you are forced to buy others to get 'everything in tree' achievement.

Later on:
Water > Earth at 201 waters

Ascension > Earth at 11 ascensions and is generally best in slot long term.
With 2 respawn accessories start you can evenetually ascend nearly instantly so you can raise the count at incredible speed if you really want to so nothing can really remotely match the potential of ascension gem.

BUT there is also the fact that gems don't matter on units other than final 5 + water(where gems improve other units) + a few others
On such useless units technically best is light but practically it hardly matters, don't bother.

Best MC forges:
MC forges highly depend on you wanting to idle or manual'ing.
Generally requires autoclicker to be remotely useful unless you go full idle.

I will mention all noteworthy stuff:

Main weapon
Best active weapon is Staff. With autoclicker and other stuff which improves it - it can multiply your unit DPS by ~400-1000%+ depending on how far into game you go...
Most bonuses to damage do NOT increase staff DPS, only ones specifically improving staff do.
This allows the manual damage weapons eventually surpass the staff... but it will only happen closer to when you finish getting all achievements in the game.

Best idle weapon is Bracelet. It will give a pathetic ~5% unit DPS increase BUT is fully idle.

Another noteworthy weapon is Pickaxe - it is best for manual damage but manual damage sucks for a VERY LONG time until you use ultimate manual build.

Sub Weapon
Cursed orb is the only useful idle sub.

Another noteworthy sub is tome of power. It's part of powerful manual damage setup but does NOT work on staff. Damage boost stacks witch each right click
Hence this is exclusive to ultra late game manual dmg setup where you click the power tome at insane speed while maintaing heat of laser as high as possible.

Trinket
Early on Coin is what you will use. But despite multiplier looking high - dev was very stingy on ore find stacking and most ore multipliers including this are additive so it becomes garbage quite fast.

Later on Clock for respawn of enemy is by far best in majority of situations unless you push ultra far beyond your auto damage which is usually not worth.

Ultimate manual build requires light(crit chance)

Most units have 1 upgrade which is by far better, I will mention any extra info required when this is not the case.

Water - generator by far, GEM MATTERS ON WATER AS IT BOOSTS ALL UNITS instead of the water itself.

The generator makes water the only important unit throughout the whole game. Other units aside of final 5 get outdated super fast.

Miner - chests have lower rate via ascension boosts so I would say they are a bit better to get.

Drill - power drill

Fusion Bomb - radioactive isotope

Magic Acolyte - fully useless, skip this

Laser Drill - fully useless, skip this

Matter Condenser - alloy is overall better to have not to bother. The way alloy works is it makes crafted items be stronger at same tier by said amount of tiers. It does not give you higher tier but trust me it works, I tested.
Ore might seem like a huge multiplier but it's additive with most ore find multipliers so it's garbage.

Temporal Beam - Warp, respawn time is HUGE deal. It in most scenarios will be better than offline ore gain even IF you are offline.

Spatial Expander - storage is usually better as it's one of the 'separate' ore multipliers.
Real estate has use when you are going for unit count achieve, will be a must for the 300 of all units achieve.

Mage - staff improve if you use it. Otherwise useless.

Universal gateway - hidden eye.

Matter Disruptor - useless if you use perks to remove forge minigame.

Matter Disassembler - both have uses.
Blue flame speeds up essence grind if you want to do it by insta crafting unit item and selling it.
Reconstructor is a tiny ore gain income BUT this boost applies to red/green/yellow ores too which is pretty powerful.

Paradox mender - pocket watch is better but not needed full time, only during boss kill. Has a bit misleading text. What it does is give you chance for boss to respawn which makes you get extra pure ore. This chance can trigger infinitely, albeit it's unlikely you will reach higher than ~15%
The other upgrade is insta kill chance... I imagine it can have use for some crazy pushing with autoclicker but it's otherwise meh.

Endless maw - purity is better but it's not important unless you get some crazy ascension count. It takes A LOT of ascensions to match even grand magus and top 5 units are MUCH further.

Grand Magus - grimoire IF you are using ultra late game manual dmg strat. Otherwise useless.

5 deities below all require ascension gems since they are your main dmg source.

Power - most important, a HUGE damage boost. You will use unit one for majority of the game, only ultra late game manual/individual is better.

Exchange - both are useful. Item cost is what I usually sit at. Unit cost is something that's usually more useful for achievement of unit count.

Precision - the most useless unless manual'ing. Take unit one unless you do manual ultra late build.

Bounty - both are very important.
Gold is best when you are farming stuff you can one shot with 2 respawn items.
Ore is absolutely massive ore gain boost.Mandatory for long pushes. Sadly it's not compatible with offline play due to how it works.
The way it works is that it only 'triggers' BUT does not get accounted in any way in the statistics, hence your 'statistics' income remains same but your 'real' income is much more massive.

Luck - item from treasure being stronger is neat... but RNG and rare.
Eternity gain is top tier but only required before you ascend. Eternity gain text is wrong btw. It ALWAYS increases your gains but it has ~50% chance to skip 'purchase' phase and instead turn all crystals into 'unspent'. You can use export/import savescum to bypass this easily.

Ascension is the usual soft reset mechanic of idle games which improves you long term.

Everything resets aside of gem unlocks(those stay purchased in tree of life), achievements, ascension perks/currency(duh) and gilded upgrades(for premium currency) and prem currency itself.

Unlike other games - ascension in this one isn't as huge of a boost as usual so you don't want to do it too early as you will gain nothing.

Instead the first ascension is reached quite fast(if you know what you are doing - you shouldn't have problem ascending 1st time in under 6 hours) if you are active and there isn't really more content than that, so it kinda makes sense that it's not boosting too much with how fast and easy it is.

Basically what ascension does is simply allows you to claim the ascension currency and spend it on perks.
Each unspent ascension currency is +1% damage. Each perk does what it's told. There are no bonuses for ascension aside of that... unless we count Endless Maw unit forge item which scales heavily based on ascension count.

Unspent currency can NOT be spent later so try to maximize your spending on better stuff early on.

Things to do before ascension:
1) Reach AT LEAST 22 ascension points, but I recommend 32. You can easily gain much more BUT if you plan to keep playing actively for some time that day - 20 is enough.

2) Do the following achieves:
Reach tier 100

Do 1 quad DPS - if you can reach tier 100 then this is easily done via Staff + mage staff multiplier upgrade and using any autoclicker.
If you are having trouble even with autoclicker for some reason - wait until 'crit orb' shows up, it essentially doubles the damage for a short period of time.

Get a total of 1k units - yet again shouldn't be a problem if you up the useless stuff.

3) Before you finally decide to ascend - try to get as many easy 10/25/50/100/150/200/300 unit milestones. Don't go out of your way, only do the ones that will take a minute at worst. This gives achieves which help next ascend a bit.

4) Before you actually ascend - make sure you have time to actively play. If you are planning to go offline/sleep soon - I recommend just putting game offline as end of ascension is the best period to 'afk' as you are kinda hitting the bottleneck of your progress and amassing ascension points at essentially your maximum speed.

There are 2 main min max methods of going offline if you plan to go offline:
1. Simply craft the offline ore item(temporal beam has it) and shutdown game.
HOWEVER before you shut down game this way - make sure you autoclick your staff for ~10 seconds. Then close the game while the autoclicker is still going at it. This will ensure your game saves an 'amplified' result.

2. Assuming you can leave your PC running - simply set the autoclicker to work with staff as your weapon for maximum profit.
This method is nice since it allows you to get the prem currency which is required for IMO among the hardest achieves of the game.

Ascension perk order:
The most important early perks are the cheapest ones:
x2 ore > egg x1
After that I recommend ore to ~x4-5 and unit dmg x2
After those I would probably invest into chest/rich stone/gold chances.

Do not go beyond egg 1 IMO, I will later explain why.... 2-3 tiers are okay if you really want to but it only saves a few seconds ultimately.

After that you should know enough to know what to take for your playstyle.... alternatively check my 4+ ascension recommendations.

Prem currency/gilded abuse:
Prem currency is farmed via random chance passively. Whenever you destroy a rock there is a chance either a 'rich rock' or 'chest' appears.
There are a few items to boost the drop rates for that but it's generally ultra rare.

You can get 30 instantly for free by following the links in the information tab(the tab near achievement one)

The only thing that's worth buying for prem currency is Gilded. You need 10 of every different unit as gilded for all achieves.

Gilded abuse:
Gilded is a pretty big multiplier bonus especially for the first few purchases since it's a separate multiplier. Albeit it's additive with itself, hence stacking too many will make the change less and less noticeable. But it's likely you will finish getting all achieves before that can happen.

The main problem is that essentially every single gilded which is under the 'endless maw' is pretty useless as you will rush until those ultra fast via achieve/ascension bonuses alone and all the older production units become obsolete as you reach higher tier.

Both Endless Maw and Grand Magus units are on the other hand covering quite a solid playtime regardless of your ascension due to how big the requirement spike for final upgrades are.
Both are viable since Endless maw gets a forge upgrade which gives huge bonus per ascension and Grand Magus is simply 1 tier higher hence it's better gains by default.

Now onto the abuse:
The gilded you get when purchasing are random. And it's not fake predetermined random which some games do in such cases.. it's TRULY random. Hence we can save scum it.

The process of gilded savescumming goes this way:
1) Go to settings and click 'export' button.
2) Go to gamefolder and find the save file that the game created there when you clicked that button.
3) COPY this file anywhere OUTSIDE of this folder. The file gets deleted from the game folder the moment you import but it's safe if it's somewhere else.
4) Buy gilded and see what you get.
5) If you are satisfied it's obviously over but if not - hit 'import'.
This should close your game AND delete the exported save file BUT make this imported save file your main save instead.
6) Relaunch the game after importing the save file and you should be in the state before you spent the prem currency.

What to accept as gilded?
First time I would say priority is:
Endless Maw/Grand Magus > Units which you don't have yet if you are on your 1st ascend.. and yes, you can get the gilded on units you didn't unlock yet.

On later ascensions I would say the final 5 units become much more important since if you follow guide you will soon be starting with them available within ~5-10 minutes of ascension.

Ultimately however you want 10 gilded on every unit which will likely be your pre final achievement... what this means is that after you got 2-3 in the good gilds I would probably stop save scumming until you start getting close to 10 on some unit at which point your new savescum will involve avoiding the units which have too many gilds already.

Don't bother going much beyond 10 gild each as the unit dmg is only needed for rushing ascensions and best method for final achieve pushes is the manual dmg build.

Your main ascension goal now is to reach the 10 sextillion blockade.
With 2 ore find purchases it shouldn't take long.

Unlocking each new unit costs 1 pure ore and they start super cheap.

5 pure ore in total however means you should limit your perk purchases to 1 unit dmg, 1 ore find and 3 forge shorteners.

All 5 units have equal power and instant access to perks.
Best perk

I would say good goal to end ascension is 50 of every unit achieve.

From now on - each time before you ascend you want to create a deity of luck forge item with all your cash and make it legendary.

This guaranteed increases your eternity crystal gain BUT has chance to skip the 'purchase' phase and add them to the pool of +1% dmg. Hence export the game save file to ensure fail doesn't happen.

3rd ascensionmain goal should be the achievement 'unlock everything in tree of life'
This means 1 of every upgrade INCLUDING the pure ore ones.

This costs 14 pure ore(9 top row and 5 units) which is boss 140 IF you don't save scum or get lucky with the double pure ore forge item.
Reaching 130 is fast but 140 can take a while,

This achieve not only gives 1000% DPS but ALSO makes you keep absolutely all tree of life unlockables upon rebirth INCLUDING the units which means you don't need 5 pure ore on that anymore.
The only ones not kept are the 9 upgrades on top.

End ascension there as getting in this one further would be a pain.

Don't forget more eternity currency forge item of luck deity unit in the end.

Ascension 4+
At this point you saw pretty much all game has to offer... aside of maybe dungeon if you were skipping on that.
Your ascension starts should be ultra fast thanks to achieve above.

Your usual start is rush minimizing the craft clicks required to fast craft everything with item level + item cost discount items.

With max lvl 10 craft you craft instantly which is by far best improvement out of all pure ore perks.

How to proceed from here?

Well, here is my recommended order:
1) Fast ascend until 25 to grab all ascend achieves and massively improve ascend gems.
Most min max fast ascend revolves around rushing until instant craft via pure ore followed by 1 point into ore/dmg/item cost/item tier.

End each run with all resources into eternity item forge.

To give you an approximate - those runs should usually end on tier 130-140 and yield ~140-175 crystals augmented by ~30% eternal crystal item to reach ~200 crystals

Closer to end of those 25 runs your main limiter becomes how many crystals you get since you can't use unspent crystals.

2) Focus on doing dungeon achieves and staying where you are still instant killing for max prem currency farm while at it.
The reason I didn't recommend dungeon earlier is exactly because it was more optimal to focus on main game to build up prem currency gains.

On slow ascensions I would invest 10 pure ore into instant craft then 1 into health/item cost/dmg and then start throwing all into dmg.
The reason I skip ore is because for some reason this is not unique multiplier hence it will likely be ~1-2% increase instead of 20% in end game.

Best ascension perks:
I would probably keep prioritizing approx equally unit dmg/ore gain/all 3 green nodes.until ~300-400 crystals in those.
Ore gain becomes low priority quite soon since price scales so slowly and once it gets higher - another 100% is simply not doing much when all it does is get you from 1400 to 1500% for example.

Also dedicate a few runs out of first 10 ascensions towards crystals and ~3-4% per crystal damage alone.

Egg is a bait in a way, avoid it - the amount of levels you can realistically get in the egg before getting all achieves only skips seconds to maybe a minute of gameplay assuming you have x2 respawn items inherited and even bother investing up to last egg before it costs over 1k.
EGG HOWEVER HARMS YOU POTENTIALLY for long push - if you inherit the + double pure ore chance item the levels which egg skips give a fixed +1 pure ore, no RNG to get 2+.
Not critical obviously, but every little bit counts.

For total end game requirements - check ultimate manual build section.

Ascension item inheritance:
The way item inheritance works is:
When you 'purchase' it - it allows you to select any of your items to inherit.
This item will be autoequipped from get go on every rebirth

There are IMO 3 most viable candidates:
2 respawn items(MC trinket + Temporal Beam unit) and pure ore double chance.

The respawn items profit early part of ascensions the most since you are instant killing anyway.
Pure ore double chance is an extra potential power you will miss if you don't inherit this. It's more important for longer run stays.

Be aware that changing item involves paying the same amount of crystals each time!

While ascension 4+ covered most things I wanted to mention what are your long term goal to be 'done' with all achieves.

1/5/10 of each gilds - 10 is likely one of longest unless you leave game idling in the background a lot with instant kills and 2 respawn items.
Chest/rich ore find/gold gain all improve the gains.
IF you use all the above you will be able to do this quite early.

All 3 of those give +1000% DPS each so worth a savescum whenever you are close.

All tree of soul achieve - this includes 1 of each item inheritance.
Try to get this achieve done ASAP once you see you can reach 1k crystals in a long run.
It gives 1k % DPS.

300 of each unit - by far longest.

Here are main tricks for this achieve:
1) The only build which works for pushing is ultimate manual build, I made separate section for it.
You should get enough ore at ~tier 291-301 with ~5-10k gold worth of 24 hour skips.
Main problem is that even if you are killing super fast - you need ~40-60 hours worth of currency to push 1 tier higher when at 291.
2) Use 24 hour timeskips while maximizing your gains with manual autoclicking since the moment you stop autoclicking your ore gain drops down so you NEED to be on prem currency tab.
3) Alternative is Dungeon with vampire/SW class. Dungeon gains eventually far surpass normal ones, around floor 300+ or so with all achieves you should notice breaking even vs 'ore' build. Vampire class can push infinitely with no skill required....
This is most optimal method.
4) Obviously don't forget x2 unit discount forge items when wrapping up.
You will need ~100-150 sexdecillion total with those 2.

Dungeon tier 200 - the most annoying if you don't enjoy it. Dungeon section covers enough to let you understand all you need to know to rush it.
To summ it shortly: rush unlock either E class or SW class.

This build revolves being in ultra late game and having stacked Red ore resource item damage + crit multiplier of your own character to the limit you can easily afford, shouldn't be hard to get upgrades until ~400-500 cost at which point it's already much better than any unit build can be.

This changes your priorities a lot.
5 unit gems no longer matter aside of power which is now individual.

The max damage of build is via:
1-3) Main weap - pickaxe
Sub - power tome
Trinket - light

4-5)
Grand Magus - Grimoire damage
Deity of power - individual damage

All 5 above require ascension gems

6) Precision - individual crit multi can be ANY gem as it boosts unit.

7) Pure ore - x10 on instant craft, ~x5-10 on item cost and the rest into red ore(activite) item levels.

The rest of the units are same as unit build except water no longer matters.

Recommended stats for 300 of each unit achieve if going without dungeon:
~50-100k crystals unused.
~250-400 ascensions.
~10-25k gold saved up for 24 hour skips if you don't plan to dungeon.

Crit multi + damage per crystal + red ore damage as close to 1k crystal cost as you can bother with... I would say going further is 100% not worth.

To farm this you need to do ~5-10 minute ascensions for max profit per ascension. Basically this means reaching place where you no longer instant kill.
And finish via full resource spending on eternity profit item.

Gild ultimately do not matter much beyond early push as units do nothing.

How to use build:
The goal is to set up a clicker for RMB > LMB spam

This has to be done on the premium currency tab so you can instantly click 'skip 24 hours' while game has your profit at maximum value... which is at ~10-15 seconds of good manual spam.

Dungeon is a game within a game.

I would say it's roguelike - but your only 'improvement' over runs are new classes.

It's a game mode which you can't ever get better at via main game so it doesn't matter when you start it.

The reward for doing it is ore for killing enemies. The amount you gain depends on your current average gain in main game AND bonuses from dungeon achieves AND possibly options on dungeon gear AND based on how far you are in the dungeon.

Also you get pure ore on every 100th floor.

Early on you will gain negligible amount of ore but if you manage to get all dungeon achieves and generally get far - the dungeon gains will surpass normal gains.

Dungeon strategy:
How dungeon plays out depends highly on class you have...
Hence this section will be more of a general info.
I will give class details further below.

All classes have 3 gear slots(but not all can realistically use them all actively)

Those 3 slots are:
Main weapon(red) - LMB by default
Main weapon is usually a spammable attack.
My only recommendation is to try each new one and see which you like.
I personally think melee weapons are pretty useless.

Depending on class my go to choices are usually plasma wave, flame wheel and plasma bomb.

Secondary weapon slot(blue) - this slot is USUALLY some form of attack OR pet summoning. RMB by default.
There are some potentially good sustain options here - for example a big circle around you which makes you stand on one place while still having ability to attack and lifesteals 1 life from each enemy quite fast.
Also a blood projectile which can steal 5 life if it hits but if it misses you lose a lot of life.
Pets usually take 25/50/100 max mana to summon and deal damage in some way.

Ability slot(green) - this one varies a lot. It's usually either a dash or a buff or some form of temporary invulnerability. Space by default.
Dashes/temp invulner are usually obvious.
Buffs usually take ¬20 max mana or health
One of my favorites on mana consuming classes is energy regen for example.

Nearly all buffs/pets which take max mana/health can be stacked infinitely, their bonus is always additive.

Modifiers - each gear can hold up to 4(maybe more, but natural soft cap seems 3 after which you will usually only be able to get more via +extra effect) modifiers. Those are passives which always work.
You can tinker with those in shrines which appear quite often.

There are 3 main things I need to tell regarding those:
1) Modifiers have tiers - you can't check tier numbers of those BUT the flame left of the option has bigger size if bigger tier.

There seems to be a limit to tiers past ~floor 100 items so at that point you should mostly start finalizing gear via rerolls/extra effects rather than relying on chests.

2) There is a 'flight' passive - I would say it's very useful for most non nigh immortal classes since not only you can move over more terrain allowing more maneuvering but you also do not take damage from traps/spiky terrain.

3) You will often find yourself in situation where you do not want to use shrine because what it does will likely be harmful BUT it's good idea to always use those regardless because shrines often have multiple uses and next option might be something ultra strong like add extra modifier.
The trick is to open chest of this floor and use crappy shrine options on useless gear piece.

Dungeon stages:
First 100 floors consist of 10 unique 'biomes', each with own boss and regular enemies.
Each biome consists of 10 floors where last one is boss.
Those biomes/floors have 'fixed' enemies and the looks of an area.
There are some pretty annoying quite dark areas which I consider among hardest due to how dark they are - the 41-50 and ESPECIALLY 51-60.
My only suggestion is to avoid playing when it's sunny outside in real life and even better if you play in a dark room in general.

On regular floors you do NOT need to kill a single enemy - it's enough to reach the stairs.
On boss floor stairs are blocked until you kill boss.

Each floor of the dungeon is nigh guaranteed to have at least 1 chest with gear.
There is also decent chance for a floor to have shrines which tinker gear modifiers.

There is no real reason to keep killing enemies unless you are not playing one of the technically 'immortal' classes. In which case kill those who endanger you or kill for a chance to get HP recovery.

The dungeon stage system changes after floor 100
The following happens:
1) The biomes become unique looking but random.
They are ALWAYS bright and ALWAYS wide. So no more narrow corridors and dark rooms - you can choose weaponry with that in mind.
2) The enemies are randomly decided from all of the 10 biomes when you enter the biome and stay consistent for the next 10 floors.
3) The amount of enemies increases but their stats remain same. Hp of some lower depth ones might have increased but I didn't notice big difference overall.
I didn't really notice much change in regular enemies every 100 floors overall. They might get some tiny stat bonus but that's it, it's not something too noticeable if it's even there.
4) Amount of bosses increases by 1 for every 100 floors. So 110-200 will be 2 bosses, 210-300 will be 3 bosses and so on.
Bosses are decided fully randomly. So if you are unlucky you can get multiple floor 100 bosses.
5) Amount of HP of bosses rises pretty noticeably, especially the lower floor ones. But this only seems to happen once at floor 100+ and after that only amount of bosses rise every 100 floors... so it never becomes too hard if you can handle 1 more boss at same time.

There a total of 8 classes you can pick from but 7 of them need to be unlocked first.

If you hate dungeon content your fastest way to get it's achievement is by rushing the 'E' class - it takes the least time to rush

You start with default one.

Once you lose once - you will see what I mean as you will be in a room where you can pick class even if you still have only default one.

I will hence name them: N/NW/NE/W/E/SW/SE/S

It's their locations in the circle with N being default class.

The way classes are unlocked is:

1) N - default

2/3) NW/NE - lvl 10 boss killed with N class (can only confirm reaching floor 20 and failing boss there but it should be boss 10 kill)

4) W beat lvl 30 boss with NW class.

5) E beat lvl 30 boss with NE class.

6) SW - lvl 60 boss killed with W class

7) SE - lvl 60 boss killed with E class

8) S - floor 100 boss killed with BOTH SW and SE classes.

Class playstyles:

1) N class - 100 HP/MANA, no gimmicks
Starter gear: ranged projectile pistol weapon.
A class which allows you to experiment with a lot of abilities since it has essentially no limitations.

Majority of other classes are straight up better so you probably better just give up the run once you get to floor 11.

2) NW class - 100 HP/200 MANA, you CAN'T get mana in any way.
Starter gear: pistol weapon you can't use + secondary attack skill - Mugen.

Mugen is essentially a pet which takes 100 Max Mana hence you can summon 2 by default.
It stays behind you and the weapon it uses depends on what you have in main weapon slot WHEN you summon it.... you can for example summon weapon you want then replace it with weapon which has better passives and as long as you don't unsummon pets - they will keep their original weapon.
Potentially is extremely powerful but it is hard to improve survivability with.

Better weapons are usually super high mana cost big range ones since pets can spam those like mad. Fire wheel is my favorite.
Generally take stuff with abilities that can help you survive, like life on kill.

Great buffs are max HP sacrifice ones which add either energy or damage... 3 pets will MELT everything with good weapon.

Not a bad class but there are better... unlock next class and move on.

3) NE class - 100 HP/25 MANA, Main weapon doesn't consume mana BUT you need enough max mana to use weapon at all.
Starter gear - melee punches

The trick of the class is to get some flat max mana increases and using high mana cost weapon for free. Getting to 50 mana for free flame wheel is the dream.
Until then just use whichever high range weapons you can.

Alternatively with extra flat mana you can keep using low mana weapon BUT use some damage buff for max mana.

Not really useful beyond being a transition class.

4) W class - 100 HP/5000 MANA, yeah, not a typo. Mana does NOT regenerate. Instead your mana refreshes to full each time you change gear. Mana can still be restored from kills however. Do not rely on this too much though.
Mana from gear modifiers is ~X10
When you change gear - previous one instantly disappears permanently.
The buffs which should cost max mana take max HP instead.

Starter gear: Fireball

Plasma bomb at max charge is by far most mana efficient weapon and it's also top tier boss killer weapon. It sucks at narrow maps but you kinda have to bear with it.
If you get some HP sustain like per kill recovery

Class is kinda so so, among the worst - you have kinda infinite mana to spam attacks at full efficiency BUT at a cost of having to not spam attacks mindlessly and occasionally forced to swap gear or risk running out of mana.
Leads to best class however.

5) E class - 10 HP/100 MANA, your MP acts as HP for taking damage.
Starter gear: pistol weapon + invulnerable shield buff.

Many strategies work to make you nigh immortal on this class.
The main idea is to not spam weapon too much and using low mana consumption weapons in general - my favorite option is plasma wave. Most non boss enemies can't get through your MP regen unless they gang up on you.

Great gear modifiers are max MP. Pair this with max MP converting to MP regen buff ability to essentially become immortal when not using mana for something else.

One of the strongest classes. Once you get good modifiers and MP regen buff - you can literally run through areas ignoring monsters and only fighting bosses.
It's not as good as SW class assuming optimal gear BUT it has an easier start and can still beat 200 waves just fine if you are too lazy to unlock SW.

6) SW class - 200 HP/100 MANA, MP does NOT regen, your HP is consumed when firing weapon but you life leech if you hit enemy.
Your pets also get lifesteal.

Starter gear:
Pistol + blood letting(HP steal bolt)

Main weapon can STOP firing if you don't have enough HP.
This makes it possible to get stuck if you spam attacks mindlessly.

Mugen also consumes your HP, so can't trick game with that one.
Main strategy is IMO having plasma wisp pets. Those fire ultra fast from range and steal 5 per shot.
Add max HP/Mana with gear ideally to be tankier AND getting 1 more wisp per 50 mana.

My favorite main on this class is plasma wave - you can pointblank with it with plasma wisps and be fine.

One of strongest classes, arguably strongest but slightly harder to get it going compared to mana shield one. Can't play it as braindead early on but utlimately is much stronger
I managed to reach 350+ HP/200+ mana by floor 200... at this point it was overall better than energy shield class and I could probably keep going infinitely if I cared.
I did reach 320 and nothing remotely had chance... and it wouldn't ever with how scaling works.

7) SE class - 75 HP/125 Mana... class gimmick is the fact that you can regen both HP and Mana BUT only one at once with HP being priority.

This sounds cool but is not as cool as you might think since HP regen isn't too fast and being unable to get mana if not at full HP sucks.

One possible strategy is getting to 200 mana and using mugen x2 with fire wheel weapon.. which makes it kinda like mugen class but with HP regen..

Can honestly even use mugen x1 too.

Generally you want mugen + firewheel + max energy until 200 and maybe some max HP to be safe from one shots.

I wouldn't bother with this class unless you really want to unlock all classes and hence need to reach 101 with this one.

Both E and SW class is better than this and last one anyway.

8) S class - 666 health/100 mana.. BUT all your health is locked and you die from 1 hit.
Any Max HP increase does nothing...
Any buff which should consume HP costs mana.

Starter gear: pistol+blink+flame guardian

Yeah, only downsides and no upsides at least out of time I tried to play this class.
I assume this is a class for those who seek challenge... but honestly with how many random enemies are on floor 100+ you kinda don't have much chance without save scum.