Shoot guy, get new gun. Get required kills with all weapons to win.

Caveats:

• Only kills with the weapon counts. Punch/dive/prop kills, and kills from other entities (such as exploding barrels or projectiles you shot), do not count. By default, goomba stomps and telefrags count and kicks do not, but this is configurable across servers.
  
• A Dishonorable death will make you lose a level by default. This only counts if you kill yourself with your current weapon. Regular suicide (fall damage/environmental hazards), suicides that happen after you advance to the next stage, and enemies using your weapon to kill you (like friction grenade / satchel / shock rifle ball) do not count as dishonorable.
  
• No down-levelling others, unfortunately. You just have to do it faster.
  
• The ordering of the weapons in this guide, as well as kill count, is the default setting. It may change over time and unofficial servers may have their own list. The advice should apply regardless.

• Shift to dive. You dive in the direction you are moving, which means you can't dive another direction if you are already mid-air.
  
• Kicking is a good way to soften an enemy up and get them out of your face, but if you kill with a kick it does not advance your current weapon (by default).
  
• It's far better to die than to risk a dishonorable death for a kill. The latter will set you back way more than the former.
  
• All melee weapons (including fists and kicking) are capable of headshots. Try to go for them if possible, especially on the crowbar and rocket crowbar, both of which are instant kills.
  
• Explosives have incredible radius in JB3. Do not underestimate them.
  
• Grenades inherit your own velocity. That is to say, if you are strafing left, expect the grenade to fly left from your cursor's point of aim. Be very mindful when strafing and throwing grenades so you don't blow yourself up.
  
• Projectiles that bounce (scientists, grenades) are affected by jump pads. Because jump pads have the same trajectory and tends to land somewhere with people, you can fire projectiles at them to kill people using the pad or on the other side.
  
• Vertical jump pads are a great place to goomba stomp. It's also a great place to be stomped on, so be careful!

3 kills required

It's a P90. With 50 rounds, 25 damage per shot and a high fire rate, it's the easiest weapon to kill with.

Hold left mouse button and point in general direction. If you're not confident in your tracking ability, you can sweep the point of fire back and forth to try and land lucky shots on a strafing enemy.

Since this is the very first weapon, you are most likely to be spraying each other with the same gun. Other than getting good, it may be easier to find someone engaging someone else and thus isn't strafing against you.

2 kills required

Diet P90 with only 30 rounds and slightly reduced damage (15 to 25), but otherwise similar characteristics. Alt fire to toggle between gangster mode, which makes recoil entirely sideways and has a very cash money reload.

I find the sideways holding type to be better against people who are strafing at close range, but it is very much up to preference. Pull trigger and point in direction, although be a bit more judicious about your magazine since it's easy to run out before killing 2 people.

brrt

Rocket goes boom. One shot, and pretty generous splash damage. You cannot rocket jump with this.

Since it's an easy weapon to kill and you only need one, try to make it count. Try to engage enemies below you or close to a wall, so that splash nets an easy kill. If the enemy is too close, it's better to die than to risk suicide and having to get 2 more kills with the CMP-2A.

Try to avoid low ground and nearby walls. If you spot a rocket launcher user about to score a kill, you can take advantage of that as their next weapon can't kill quickly.

Ricochet time baby. Left mouse throws the disk, which is a relatively slow projectile that does 28 damage and absurd knockback. Disks thrown this way will come back after hitting the first enemy or surface (and deal damage on the way back). Alt fire launches an explosive disk that has a small lethal splash. The explosive disk is not recoverable, but this doesn't matter for gun game.

Secondary fire is much easier to kill with, so after you get the disk, immediately start holding down right mouse to charge it, and release once a target is in range. Feel free to finish up wounded enemies with primary attacks. The explosive disk goes slightly lower than where your cursor is, so be wary of killing yourself with it.

With a slow projectile, it's easy to strafe around disks at medium range. If you spot someone throwing a single disk after a small delay, it's likely explosive - try to dive away.

2 kills required

A highly accurate pistol with good damage (35), able to one-tap with a headshot. The silencer makes this weapon's firing sound inaudible to others and tracer invisible. With a low clip size of 10, it's a weapon that can you can choke on easily.

10 rounds is enough to get 2 kills, but not if you are careless with tapping. Going for headshots is best, but 3 taps from the silenced pistol is pretty fast and should be your preferred way to fight. Since this weapon is perfectly accurate, you can also pick off people at a distance.

It can be hard to tell when someone is shooting at you with the silenced pistol due to its nature, and often you die immediately from a skillful or lucky headshot. De-prioritize silenced pistol enemies unless you know they're not a good shot.

2 kills required

A slow but powerful shotgun, firing 6 pellets that do 28 damage each. You have to click again after shooting to pump (unless you reload). Alt fire shoots bouncy bullets in a tighter spread, but the damage is the same and it costs 3 shells.

Avoid using alt fire as the ammo cost is prohibitive and gives no additional damage - plus, this weapon is perfectly capable of picking off targets at medium range. Despite its status as a shotgun, it has a pretty tight spread. This, combined with the punishingly slow cycle time, means you really can't afford to miss.

This weapon is best at medium range, so either stay very far to mitigate damage, or very close to juke shots.

A quirky weapon that fires explosive scientists. Primary attack fires a bouncy one and secondary attack fires a sticky one. The bouncy scientist flies slightly further. Both will lethally explode on contact with enemy (or yourself), otherwise they will say a random line before exploding, making fuse time vary significantly. Blast radius is large, but not lethal unless very close.

Be very wary of suiciding with this weapon! Maintain medium distance and try to go for impact hits. If there are narrow hallways, fight around them to make impact shots easier. Use primary fire if there are corridors to bounce into or if the enemy is on the far side; use secondary fire if you are interrupting other fights so that the explosion happens near the fight.

The weapon has a slow, predictable pace so try to anticipate and evade shots using dive. Stay away from narrow hallways and walls to avoid bouncy scientists, and keep distance for sticky ones. Fighting at long distance is also a great tactic, as the scientists can't fly very far.

2 kills required

Lock, stock, two smoking barrels. Does a lot of damage and sends you flying like the Force-A-Nature. Alt fire is a melee butt whack that does 30 damage and sends the enemy flying.

The insane damage on the DB makes it easy to kill even at close to medium range, so don't be afraid to take a potshot. The melee is not typically needed, but since the launch angle is pretty consistent, you can pop someone into the air and take them out like Duck Hunt. Since a single shot can kill, you can use the self knockback to traverse the map and close the gap to follow up with the second shot.

Stay away and be afraid. Or don't, since beefing with the DB is a tale as old as Doom.

Hit the enemy with a melon. Primary fire is a fast melon and secondary fire is a slow, zero-gravity melon; both will kill on contact, and bounce off walls several times.

Primary fire is much easier to kill with, so practice with the projectile and treat it like a big fat crossbow. The alt fire may be good in chokepoints where people can walk into them, but you can also kick the melon yourself. Just be careful not to walk into it and die. Also be wary of the ricochet killing yourself, and avoid firing straight into a wall.

The melon blunderbuss only has a single shot and a noticeably long reload time, so if they just fired, you can go in for the kill. The melon is incredibly fast, but you can kick it to send it backwards if you get the timing right or got lucky spamming kicks.

2 kills required

A good old fashioned pair of pistols. Not too accurate, but deals a respectable 46 damage for a 3 shot kill.

The low accuracy means you need to try to get up close for kills, so do just that.

Stay at longer ranges so that the poor accuracy hurts real bad.

A cannon that launches you backward with incredible force, easily able to keep you mid-air indefinitely. Has no reload and an incredible blast radius, but blast damage is low unless you hit accurately (up to 70 on impact).

This can be one of the harder weapons to kill with. Due to its knockback and projectile nature, landing accurate hits fast is hard. You can either fire rapidly, launching yourself into the air and hoping to catch someone with the large blast radius; or to fire infrequently to hit accurate shots for 60 a piece. On more populated servers, the former is likely easier; otherwise you will have to aim those cannon shots.

It's usually not worth fighting against anti-air cannon users as they are knocked all over, making hitting them harder than usual. However, in the event that they backed themselves into a corner, they will be incredibly easy to hit as their shots will only keep them in place.

2 kills required

It's a pistol that bursts. Primary fire shoots a single bullet (28 damage) and secondary fire shoots a 3-round burst, both of which are decently but not fully accurate. Magazine capacity 15.

Don't feel pressured to burst with this weapon, as the single shot damage is good enough to kill. Only burst if you are confident the whole burst can land, or as a finisher. Don't try to engage at super long ranges.

It's a conceptually simple weapon, so just try to outskill the other gamer.

One of the more exotic weapons on offer. Detonates on impact, turning afflicted targets into a human pinball, unable to control themselves while bouncing at high speed off any surface. They will instantly kill anyone on impact (credited to the thrower) and take damage when hitting a wall. Alt-fire applies the friction grenade to yourself, but you will take no impact damage.

Since you have infinite ammo, toss this with reckless abandon into groups of people so they knock each other out or hit the walls. Most effective when used near environmental hazards, indoors, or when there is a pit that can't be walked into. It's possible to hit yourself and suicide with this and get ungraceful death; however, having an afflicted enemy impact you does not count.

If the opportunity presents itself, you can alt-fire to launch yourself in the direction you are looking to smash an enemy in the face. This is slightly risky and may result in wasted time.

If you are hit, you will be rendered helpless for several seconds, which isn't ideal even if you don't die. For this reason, it's best to avoid friction grenade throwers altogether, and try to find elevation advantages to avoid both the grenade itself, and the people being thrown around by it.

2 kills required

A pretty versatile but hard to master weapon. Primary fire is a hitscan laser that does 60 damage - not very impressive. Secondary fire shoots a slow electric ball that splashes for around 40 damage - also not very impressive.

The magic happens when the electric ball is shot by the shock rifle (or any weapon, actually), which causes a powerful explosion that is typically lethal. Anyone can shoot the ball, and the kill is credited to the person who triggered the explosion.

The shock rifle is at its most powerful when you have the time and space to detonate those electric balls. Try to pre-fire the balls into places you want to enter, and detonate them with the primary attack once someone gets near. However, due to the firing delay, enemies that are too close can't be hit by this - in this case, you must resort to spamming alt fire to splash them. While the primary fire by itself is not strong, it is still an instant kill on headshot and can pick off enemies pretty easily.

It is technically possible, although unlikely, to kill yourself with the alt-fire ball. Try to not do that.

Many players don't know how to use the exploding ball mechanic. If you spot someone who only uses primary fire, they will be easy to kill due to the slow and typically two-shot nature of its main attack. Otherwise, you will need to avoid narrow corridors and keep distance with any orb they shoot, which is not an easy task. If you have a better long-range weapon or better aim, keeping long range can let you outgun them.

You can shoot the ball, but this won't progress your weapon unless you are also on shock rifle.

2 kills required

A big-ass Single Action Army. Six rounds, more than enough to kill anything that moves. Bullets do 85 damage and are perfectly accurate. Alt fire spins the weapon, and is kinda cool. When reloading, mash the reload key to load faster.

The revolver is a weapon that rewards accuracy and patience. It will require two hits to kill on a full health opponent. If you're good enough, you can just hit twice, but it's far easier to instead pick off injured enemies escaping from a fight and avoid people who just spawned. Alternatively, if you are super close you can try to kick and injure them first (but not finish with a kick as that doesn't count). It also has no inaccuracy, so picking off someone at long range is also valid.

This weapon is very hit or miss, and its low capacity means it's usually worth trying to fight a revolver user and hope they miss or don't have enough shots. Try to get in close and have them panic.

It goes boom. Left click to throw. Right click to kamikaze. Holding down left click shortens the fuse.

Spam throw this at long distances to catch people in fights - they're usually too busy to notice. The throwing force is high and you have no underhand throw or impact throw, so bounce it off walls and floors if you need a closer distance launch. You can also hold it to shorten the fuse in anticipation of an enemy. Suicide is highly likely and deeply punishing, so watch where your nades go and do everything you can to not die to them. Do not ever right click.

A frag grenade holder is a free kill - just watch where the nades go and be wary of them suddenly getting a kill while you're trying to finish them off.

2 kills required

An unassuming pistol. Has 17 rounds and does 19 damage per shot at medium accuracy and fire rate. Not very impressive, but its alt fire is the mighty rear gas, capable of instant killing anyone behind you and launching you forward if you are mid-air.

The primary fire is not strong, but good enough to pick off enemies. Secondary fire can instantly kill a close up opponent as long as you turn around to do the deed. You can do so by jumping into the opponent before doing a 180. Diving is also okay, but slightly harder due to the increased speed and dive knockback. You can also use the alt fire as an air dash to get to advantageous positions or chase enemies.

Reloading refreshes the fart cooldown. You can time a fart right before a reload finishes and get a double fart for extra mobility.

While most people don't know about the mighty fart, you should still keep a bit of distance and be wary of pistol users attempting it on you. If your weapon can outgun the pistol, it should be a relatively easy win for you.

A mighty explosive bag. Right click to throw, left click to throw/detonate.

Just throw and explode in front of you. The range and damage is incredible, so it's hard to not kill with this one. The velocity inheritance will make suiciding with satchels common - try to walk forward before throwing (to increase velocity) and immediately backing off to maintain safe distance.

Satchel has limited throwing range, so stay at medium to long range for easy satchel user kills.

A fun little teleporter thing with powerful AOE damage. Left click fires a teleporter ball. On impact, it teleports the target elsewhere, and then creates a massive, deadly energy blast. Alt fire teleports yourself to a random location, and then leaves an energy blast where you were.

Avoid impact hitting the ball. Splash it at the ground to kill, but be wary of suiciding as the radius is very big. If an enemy is near or trying to approach, use alt-fire to escape the fight and leave a lethal parting gift. You can also spam alt fire if you don't see any enemies to kill nearby.

The random teleport seems to send you to a spawn area or one of several map determined spots. This usually lands you near some enemies, and is generally a good thing as you will catch them off guard.

The Displacer is a hard weapon to fight. You must try to kill the user in between their shots, as the radius is large and they can teleport away if you get too close or become too threatening. If possible, avoid them and kill other people.

However, the Displacer's biggest weakness is that it has a long delay between attacking and the projectile firing, and will emit 5 beeps letting enemies know it's coming. Higher pitched beeps indicates a primary attack while lower pitched beeps is a secondary attack. You can use this information to determine whether you should approach or make distance.

2 kills required

The weapon we didn't axe for, but deserve nevertheless. Respectable 28 damage per shot, high recoil, low accuracy. Alt fire is an axe attack that does 45 damage.

The recoil, accuracy and axe component makes this weapon best at close range. Spray down your enemies, and only use the melee attack if the moment is opportune - you can kill with 2 shots + axe hit, but using axe alone actually takes 3 hits... unless you headshot.

Keep medium distance so that the weapon is hard to hit,

2 kills required

You're that ninja...
Throwable projectiles that deal 25 damage on impact. Primary attack throws 5 in a stack and secondary fire throws 1 with higher fire rate.

Spam primary attack, as it has enough shruikens to kill in one throw. As with impact projectile weapons, narrow hallways and people who don't see you are easiest to hit. You can use secondary attack if you know the enemy is wounded.

Keep a distance and avoid narrow hallways.

2 kills required

A weapon that shoots medium speed projectiles doing 25 damage each.

Despite its mediocre fire rate and damage, the pulse rifle is actually pretty reliable at medium range. It is especially deadly to prone targets or people who strafe poorly, so lead those shots and get through quick. Be aware that the bright, slow projectile draws a lot of attention to your position.

Strafe long distances instead of in place to avoid the projectiles better. The further you are, the easier it is to dodge these shots.

Deals 20 damage per shot with good accuracy and surprisingly high recoil. Alt-fire unfolds the stock and switches to single fire, make the weapon perfectly accurate and with reduced recoil. As with the silenced pistol, it has no tracer and no audible firing noise.

Switching to semi-automatic is generally not necessary, as it takes time and doesn't actually give you extra damage. If you're more comfortable with it though, feel free.

It's another spraying weapon, so try your best to strafe against shots and fight back. While not the strongest automatic firearm, it is still potent and can kill quickly, so don't underestimate it.

A suppressed semi-automatic rifle. Deals 45 damage per hit with perfect accuracy but high recoil. As with suppressed weapons, it has no audible firing noise and no tracer.

Generally, the scope is not needed due to the very high recoil and 3 shots to kill. Only go for it if you are confident you can land a headshot. Spraying this up close honestly gets results much easier.

Not much to say beside try to kill them faster than they can kill you. If a Vintorez user is sniping you, chances are they'll beef most of their shots from recoil, so don't be too concerned.

2 kills required

A pair of pistols that fire separately. Deals 27 damage with decent accuracy, and has 15 rounds per pistol.

For maximum firepower, you will need to rapidly tap both mouse buttons, but this will also make the recoil hard to manage. It's entirely valid to spend all the ammo on one gun first, and then the next, as this also reduces reload time (there is a single reload if only one gun needs ammo).

While easy to miss with, the generous capacity and firepower makes this weapon pretty scary up close. Maintain distance if possible.

Possibly the hardest non-melee to get a kill with, the railgun fires a perfectly accurate 80 damage beam with a low rate of fire.

The slow attack speed is very punishing if you do not kill on first hit. Try to pick off injured opponents or go for headshots. You can use your range to your advantage here, but the lack of a scope also hurts.

If you have above 80 health, you can confidently push a railgun user and tank one body shot to kill them. Otherwise, try to throw off their shots by getting closer.

A rapid firing projectile weapon that does 11 damage per nail. Nails fly at a relatively slow speed and are not affected by gravity.

Close the distance and spray in the direction your enemy is moving. If they are strafing, try to point the stream of nails at the center point of their strafe if they are doing it back and forth.

Strafe long distances and dive in the opposite direction to avoid the stream of nails. If possible, use height advantage and distance to avoid them entirely.

2 kills required for each

These weapons have identical stats, and fire an instant kill hitscan shot that has a chance to ricochet once.

Click on the enemy.

Don't get clicked on.

Four times the barrel, four times the fun. Alt fire to shoot all rockets in an inaccurate salvo. Rockets don't deal enough damage to be lethal (around 70-90 on impact). Can be used to rocket jump with minimal self damage (around 3-5).

Since you only need one kill to advance, one salvo into an ongoing fight is usually enough. Be aware of self damage, and rely on primary fire if there is a risk of suicide. Like the rocket launcher, you want to use height advantages, and deal splash damage using floors and walls.

Splashing someone at their feet will launch them into the air, which allows you to easily land a second shot where they land or airshot them for style points.

Also like the rocket launcher, try to get high ground and avoid nearby walls.

If you are launched, you can air strafe to try to change your momentum and dodge the second shot.

Perfectly accurate, one shot kill, takes forever to cycle. Alt fire is a scope.

Don't miss.

Don't get hit.

It's a melee weapon but also a rocket launcher. Primary attack to hurt the enemy on hit (a two-hit kill), or launch yourself if hitting a surface. Alt fire to launch an inaccurate rocket that does ~60 damage on impact.

The rockets' high inaccuracy makes it risky to use, as you can blow yourself up. Hit the walls and floor to close the distance, and then try whack them in the head. If you have to use the rockets, aim higher or ensure you are higher above the ground to avoid suiciding.

The rockets are slow, but hard to dodge due to unpredictability. Go diagonally against rockets' path and keep a minimum distance to the rocket crowbar user.

Proximity-based explosive feline. Left click to throw, right click to underhand throw. The cat will wander around until someone gets near, then go boom.

Throw as many as possible into populated areas. Hopefully you die before they go off, so you don't blow yourself up as well doing so.

The cat mines are hard to dodge (even if you dive as soon as it triggers, you will die). Close the distance to kill the cat holder, and shoot the mines or avoid them entirely.

Two hornet guns. Has a clip size of 16 that slowly regenerates over time. Each hornet does 10 damage, flying slowly on primary fire and quickly on alt fire. They have light seeking capabilities and bounce off walls a few times.

The hornet gun is just barely capable of bursting someone if you land every shot. Despite the homing capabilities, this is much harder than you would think. Try to close the distance and use the faster secondary fire to land a salvo for best chances, or find wounded enemies to finish off.

The limited clip size means that once a hornet gun user spends their ammo, they are almost completely defenseless. Take advantage of this for an easy kill.

Play loud music to hurt your enemies. Damage is based on proximity.

Hold mouse one and get close to your opponent. You do not need to aim, only survive - so be as evasive as possible. Try to jump over their heads and circle around enemies at close range to throw up their aim.

Music can't hurt you if you're outside point blank, so just backpedal. If a dubstep gun is on you, try kicking them to knock them back.

A throwback from TFC. Hold primary attack to charge up your bullet and release to shoot. Longer charge equals more damage. Alt fire zooms in. You can only shoot while on the ground, but can charge mid-air. Pressing reload switches off the charge mechanic, letting the weapon fire fully automatically at high recoil and low accuracy for 17 damage per shot.

You do not need full charge to kill - about one and a half second is enough damage to bodyshot. Try to spend as little time charging as possible, since your mobility is severely limited while doing so. The automatic mode is hard to hit, but may be useful in a pinch or if you really can't hit charged shots.

While charging, charge rifle users are immobile and easy to score headshots or projectile impacts against. Take advantage of this, especially on those who aren't actively fighting you. If they are using the automatic firing mode, their shots will be very inaccurate and so you can just back off.

A pocket rifle with an infinity-shaped magazine. Insanely high recoil but only 23 damage.

The temptation of holding down fire button is high, but with the recoil it's hard to even see what you're hitting. Fire short bursts to keep your cursor on target. Engage with as close of a distance as possible, as the gun is neither controllable nor accurate beyond close range.

At medium range, this weapon performs extremely poorly. Take advantage of this for easy kills.

A tripmine that creates a black hole. Anyone sucked into it will die immediately, and it also attracts all physical objects, including projectiles.

Place as many of them down as possible and you will inevitably get kills. Set them sideways on walls so they are triggered more easily.

Someone holding the tripmine has no way of fighting back against you, and is a pretty easy kill.

We move into the final 3 melee weapons, which require a lot more finesse to get kills with. This one is an automatic melee weapon, doing 20 damage per hit at a moderate pace.

Walk up close and start drilling. You need to find a victim who is either injured, or doesn't have a good weapon to fight back with (grenades, railgun, etc). Aim for the head for a quick kill.

If you can see them coming, it's usually a free kill. Otherwise, kick them away to keep distance.

A knife with a scope. Does 30 damage per slash at a pretty fast speed. The scope is not useless - if you alt fire to zoom in, your melee range dramatically increases and can hit people at medium range; plus, your mobility is unhindered. Backstabs are instant kills.

While you have the option to, scoping in is not really necessary as the weapon kills quite quickly. Sneak in a backstab for an even cleaner kill; otherwise you can try for headshots.

People typically do not use the scope feature, so staying back and kicking them is usually good enough. However, you need to be vigilant, as someone with the scoped knife is only two weapons away from winning, and you may need to focus them to give yourself more time.

The final weapon. Once you get to this stage, your status is announced to the server and you get an unmistakable red glow. Expect people to stay on their guard.

The crowbar itself does 40 damage at a relatively slow rate of fire. No gimmicks here.

A headshot with the crowbar is an instant kill - if you can land it. As with the other melee weapons, you do not have any option to close a gap, and must pick fights where the other side doesn't see it coming. Good luck!

If the crowbar user gets a kill on anyone, it's game over. Relentlessly focus them and steal their kills if possible. The crowbar has no gimmick and its user can do nothing if you keep at arm's length.