Lvl up
Mutations are extra abilities that are given to you at the end of a level if you have leveled up. To level up you need to get 60 Rads multiplied by your current level number, which means the amount of Rads required increases with the character's level (60, 120, 180, etc.). Each level up is signified by a white crown symbol, appearing above your character. Going over level 9 and essentially reaching level 10 (Level Ultra) allows you to choose one of the character-specific Ultra Mutations listed below the regular Mutations table.

Mutations tableEdit

Level 1
A list of all the mutations in alphabetical order. At the end of a level you can choose between 4 randomly rolled mutations per level up. Currently the game allows players to reach level 10, which means a total of 9 mutations. (Or 10 mutations if you take the Crown of Destiny, 11 if you also picked Patience)

In Co-op picked mutations will affect both characters.

Mutation Icon Description

Back Muscle

Back Muscle Icon HUD

Bullet capacity increases from 255 to 555 and all other ammunition's capacity increases from 55 to 99.

The game still uses normal capacity values to check how much ammo percentage you have and to calculate the pickup drop rate.



Blood Lust Icon HUD

Gives you a 7.69% (1/13) chance of regenerating 1 HP when you kill an enemy.


Boiling Veins

Boiling Veins Icon HUD
Boiling veins

You take no damage from explosions when at 4 or less HP. It also nullifies any fire damage.

To clarify; if you are damaged by an explosion at above 4 health, you will end up with no less than 4 health. (Explosions and fire cannot kill you.)

Melting will be immune on full 2/2 health with this mutation, but if you have Rhino Skin it will work like it does with the other characters.


Bolt Marrow

Bone Marrow Icon HUD
Arrow in the knee

Bolts and splinters seek enemies, changing the direction if close enough. Larger bolts from Heavy Crossbows will have a weaker homing effect.

Seekers will home from further away, and take much sharper angles.

Discs slightly change their direction and slowdown to hit an enemy multiple times.


Eagle Eyes

Eagle Eyes Icon HUD
Eagle Eyes Icon New

Increased accuracy, meaning less bullet spread. For example, SMG projectiles will fire in a straight line.

Reduces fixed spread for weapons like the Triple Machinegun, Shotgun, Super Slugger, Super Crossbow, Splinter and Seeker weapons, and the Shovel. As a result, their projectiles are grouped tighter together.

Steroids' accuracy will be boosted to a level a bit beyond the other mutants' base accuracy, but it will still not be as much as the other mutants' with Eagle Eyes.



Euphoria Icon HUD

20% slower enemy bullets.

Synergizes well with Eyes's active ability.


Extra Feet

Extra Feet Icon HUD
Extra Feet2

Movement speed is increased.

Additionally makes you walk normally on all surfaces. That includes spider webs in Crystal Caves and ice in Frozen City.


Gamma Guts

Gamma Guts Icon HUD
Gamma Guts2

Touching enemies makes them take 6 damage per hit animation, for as long as your character is in contact with them. You will take no contact damage from enemies that are instantly killed by Gamma Guts (have 12 or less health at the moment of impact, as it takes two frames for enemies to deal contact damage with Gamma Guts).

If an enemy is killed by Gamma Guts, your character will create an area of effect blast which deals 8 damage to all nearby enemies.

Can also be used as a last resort if you run out of ammo and don't have a melee weapon.



Hammerhead Icon HUD

Pushing against a wall allows your character to break through exactly 20 wall tiles to create instant cover, or ambush enemies. You can also break Fire Traps by walking into them.

The amount of tiles you can break resets back to 20 each time you enter a level ending portal.


Heavy Heart

Heavy Heart Icon HUD
Heavy Heart

Rate of weapon drops from enemies is increased by 210%.

If an enemy has 2% chance to drop a weapon, with Heavy Heart that becomes 2%+2*210%=6.2%.

Heavy Heart will only appear after you've picked your third "weapon type specific" mutation (Recycle Gland, Shotgun Shoulders, Bolt Marrow, Boiling Veins, Laser Brain or Long Arms) and won't appear again. It's not a part of the usual mutation pool.


Impact Wrists

Impact wrists Icon HUD

Crystal SMASH

Makes corpses fly much farther and faster, and they do more damage on impact. 

Regularly, a corpse does 1 damage on impact with an enemy. With this mutation knocked away corpses do 2 damage + damage based on how fast they are going.


Laser Brain

Laser Brain Icon HUD
Laser brain

Energy weapons have the duration and size of their attacks increased by 20%, meaning they will hit the target more times.

  • Laser beam gets wider, lasts longer, dealing 2-14 damage. Addittionally, the Laser Cannon fires two more beams per burst.
  • Plasma spheres get bigger and takes longer to shrink. A small plasma projectile deals 4-24 damage. Big plasma projectile fired by the Plasma Cannon deals 17-86 damage. The main plasma projectile fired by the Super Plasma Cannon deals 28-149 damage. Plasma Explosions are not affected by this mutation.
  • Plasma Explosive weapon's damage does't change but Devastator's trail is 40% slower, which means more explosions.
  • Lightning rails last longer, dealing 7-21 damage. Projectile fired by the Lightning Cannon deals 50 impact damage.
  • Energy Melee slashing projectile lasts longer so it can hit the target twice, and is slightly bigger.

Last Wish

Last Wish Icon HUD
Last Wish Icon New

Choosing this mutation will fully heal your character, give you 200 bullet ammo and 20 ammo for every other type. It also fills Rogue's Portal Strike ammo.

Chicken will replenish all of her lost max HP when choosing this mutation. You can also revive Chicken by picking Last Wish while she's headless inside a portal.

Choosing Last Wish while holding a Cursed Weapon removes the curse.

Entering the Jungle secret area will remove Last Wish from your character's mutations. You will instantly choose a mutation that replaces it, the mutations will be a completely fresh set as if you had taken patience. Last Wish will be put back into the pool of mutations you can choose from so it's possible to pick it again from this set.


Long Arms

Long Arms Icon HUD
Long Arms2
More melee range. Melee swings will appear further from the character and travel a longer distance. Enemies directly in front of your character will still get damaged even if the swing projectile isn't in contact with them.

Lucky Shot

Lucky Shot Icon HUD
Lucky shot

11.76% of kills regenerate ammo. The ammo type is equally random.

It gives 32 bullets, 8 shells, 7 bolts, 6 explosives or 10 energy, which is equal to that of a Mini Ammo Chest. (the in-game text is bugged and shows less)

For Fish that's 40 bullets, 10 shells, 9 bolts, 8 explosives or 13 energy.


Open Mind

OpenMind Icon HUD

An extra Ammo Chest, Weapon Chest or Radiation Canister will spawn on every level, with equal chances of appearing.

Extra Chests/Canisters can appear in different forms, depending on the conditions and chances listed on the Pickups page. Chests that appear only in Secret Areas can also spawn as extras in those areas.

If two Weapon Chests spawn on the same level and you leave both unopened, both will count towards spawning a Large Weapon Chest.

If two Radiation Canisters spawn on the same level and you leave both unopened, they will count as one Big Radiation Canister.

Playing as Rogue changes the extra Radiation Canisters into Portal Strike Ammo Canisters.



Patience HUD1
This acts as a re-roll for the current set of mutations. It doesn't do anything at first, but next time you enter a portal you will get another set of four mutations to choose from.

Patience doesn't count into the mutations cap, which means you can have 9 mutations at max level (10 with Crown of Destiny).

Patience actually skips to the next selection of mutations, meaning that no matter if you pick Patience or another mutation on offer, the next level-up has the same set of mutations. This only has a practical effect in seeded runs, though.


Plutonium Hunger

Plutonium Hunger Icon HUD
Plutonium Hunger2
Increases the pick-up range for radiation, ammo and health drops (There is less of an increase on the pick-up range on ammo and health than on rads).

Cursed Mini Ammo Chests are unaffected.


Rabbit Paw

Rabbit Paw Icon HUD
Rabbit Paw2

(Mini Ammo Chests and Mini Medkits) drop from enemies 1.4 times as often.


Recycle Gland

Recycle Gland Icon HUD

Each bullet that hits an enemy or a destructible object has a 60% chance of giving you  +1 bullet type ammo back. Heavy bullets fired by Heavy Revolver and Heavy Machinegun give +2 ammo.

Works only for Regular and Bouncer Bullet Weapons. Does nothing with Pop Bullet Weapons.


Rhino Skin

Rhino Skin Icon HUD
Rhino Skin2

Adds 4 max HP. It will instantly heal your character for that 4 HP.

You can also revive Chicken by choosing Rhino Skin while she's headless inside a portal.


Scarier Face

Scary Face Icon HUD
Scarier Face2

Enemies have 20% less HP.

Their max HP values are reduced and rounded to the nearest full number, following the common rounding method.

It doesn't affect destructible objects.


Second Stomach

Second Stomach Icon HUD
Eyes is pregnant

Doubles the health received from Pickups. Mini Medkits give 4 HP instead of 2 HP. Medkits give 8 HP instead of 4 HP.

This also affects Robot, with eaten guns giving 4 HP instead of 2 HP.

Bloodlust isn't affected by this mutation.

The double multiplier is added before the Crown of Haste effect. After taking the crown Mini Medkits will heal for 5 HP instead of the expected 6 HP. Stationary Medkits are unaffected by the crown and will heal for 8HP.


Sharp Teeth

Sharpteeth HUD


Taking damage deals 2.5x the amount of HP you lost, to all enemies currently on the screen.

Especially useful for self damaging characters like Rebel.

Damage prevented by Boiling Veins, Strong Spirit, or taking more damage than your remaining HP will not count for the damage dealt to enemies.

Fun fact, this is one of the only ways that enemies can take decimal damage.


Shotgun Shoulders

Shotgun Fingers Icon HUD
Shotgun fingers

Shell Weapons projectiles bounce further and travel faster after bouncing.

It causes Flame Pellets to bounce off walls, but the distance isn't as long as with regular Pellets and they can bounce off only once.

Also works on Pop and Flame Pop Bullet Weapons.

Normally all these weapons deal more damage up close. With this mutation their projectiles also deal that increased damage right after bouncing off walls (for two frames after bouncing, check the weapons page for the increased damage values).




Increases rate of fire in relation to the amount of missing health.

The fire-rate buff provided by Stress is inversely proportional to percentage remaining of max HP. It gives you up to +100% higher rate of fire as your health gets lower. (Normal 100% + Stress's extra 100% fire rate at 0 HP)

You can calculate your reload speed with (1 + (1 - (HP / Max HP))) * 100, so for example if you're at 4 / 8 HP you would have 150% reload.

Rhino Skin and Crystal synergize with Stress as having higher maximum HP will allow you to smaller percentages, and simultaneously receiving more benefit while being at higher HP.

Even if you have 20 max health as Crystal the highest reload speed you can have is 195% on 1 HP.

The only character that can reach 200% and not die is Chicken without her head.


Strong Spirit

Strong Spirit HUD
Strong Spirit

Lethal blows grant 5 frames (1/6 of a second) of invincibility and reduce your health to 1 instead of killing your character.

Strong Spirit can activate and save your life once per area. It recharges when you leave the level that it activated in and heal back to full health. If the mutation is charged your character will have a halo above its head.

Having 1 max health as Chicken or Melting will limit this mutation to save you from death only once. It can't be recharged afterwards.


Throne Butt

Throne Butt Icon HUD
Throne Butt2

Upgrades your character's special ability.

  • Fish: Roll for as long as the active button is held and can move in different directions while rolling.
  • Crystal: Shortens the shielding time and allows Crystal to teleport at the cursor's location after her shield disappears.
  • Eyes: Pulls enemies faster and pushes bullets away with more force.
  • Melting: Explodes corpses/destroyed objects with three Blood Explosions instead of one. The body/object size doesn't matter.
  • Plant: Vines kill enemies who are under 33% health.
  • Y. V.: Upgrades Pop Pop into Brrrrap, shooting four times as many projectiles, but the reload time is 3 times as much instead of 2.
  • Steroids: Firing one weapon has a chance to add a small amount of ammo for the other weapon. This is more likely to occur when both weapons are being fired at once.
  • Robot: Adds additional ammo or health that is equal to one mini ammo or HP pickup when eating a weapon.
  • Chicken: Thrown weapons pierce through targets.
  • Rebel: Gives allies a better weapon which increases their fire rate by 60%.
  • Horror: Horror's radiation beam gets wider twice as fast. Using the beam for extended periods of time now heals Horror (1 HP for every 1.5 seconds).
  • Rogue: Makes Rogue's Portal Strike explosions much bigger.
  • Skeleton: Adds a 1/3 chance that Skeleton won't take damage with Blood Gamble.
  • Frog: Causes all toxic gas to spread further and faster.

Trigger Fingers

Racingmind icon
Racing Mind2
Each enemy killed reduces your remaining reload time on both equipped weapons by 40%.

This only affects the current reload; it is not a permanent reduction.

Great for the Nuke Launcher, Heavy Crossbow, Plasma Cannon or any other weapon with long reload time and high damage.

The interval between swings with a melee weapon is also greatly reduced with this mutation.


Ultra Mutations tableEdit

Level Ultra
Going over level 9 and essentially reaching level 10 (Level Ultra) allows you to choose one of the character-specific Ultra Mutations. On the experience bar the number 10 is replaced by a crown icon, indicating that your character reached its full potential. This adds 1 extra mutation to the max that your character can have. That's a total of 9 mutations, 10 with Crown of Destiny, 11 if you also picked Patience and 14 if you play as Melting with his second Ultra Mutation.
Character Ultra Mutation Icon Description
Fish icon1



Fish A
Fish Ultra 1

Enemies have a 20% chance to drop an Ammo Chest (which can also be a Present Chest or an I.D.P.D. Chest) or a Medkit instead of regular mini pickups.

They can also drop regular Weapon Chests instead of weapons. Not opening the Weapon Chests counts towards a Large Weapon Chest spawn. If you have a Crown, enemies can rarely drop a Cursed Chest.


Gun Warrant

Fish B
Fish Ultra 2

Weapons don't consume ammo for 7 seconds after exiting a level ending portal.

Crystal icon1



Crystal A
Crystal Ultra 1

Adds 6 max HP. Crystal will instantly get healed for 6 HP.

Can be stacked with Rhino Skin for a max of 20 HP.



Crystal B
Crystal Ultra 2

Enables slowed movement while shielding.

Eyes icon1


Projectile Style

Eyes A
Eyes Ultra 1

While using Telekinesis, your projectiles will be frozen in a stationary position on top of Eyes, in the direction of where you shot your gun. Upon deactivating Telekinesis, all projectiles will continue to travel their initial destination and behave as normal.

Melee weapons will have less range while using Telekinesis.


Monster Style

Eyes B
Eyes Ultra 2

Push away nearby enemies.

Enemies will be pushed passively, with or without Telekinesis activated.

Melting icon1


Brain Capacity

Melting A
Melting Ultra 1

Enemies at 5 hp or less will blow up along with corpses upon using your active ability. That includes undamaged enemies.



Melting B
Melting Ultra 2

Lose half of your maximum HP to immediately get 3 more mutation choices.

Plant icon1



Plant A
Plant Ultra 1

6 Snare Growth vines appear instead of 1, covering a much larger area.



Plant B2
Plant Ultra 2
Sapling idle
Each enemy killed while snared will spawn deadly Saplings, which fly around and will home towards other enemies dealing 5 impact damage and afterwards causing 3 closely packed Blood Explosions. Each Sapling has 10 HP and can explode upon taking 10 or more damage.

Each blood explosion deals 4-12 damage and destroys any projectiles in the blast radius. Blood explosions don't destroy walls and do no damage to the player.

Yv icon1

Y.V. (Yung Venuz)

Ima Gun God

YV Ultra 1

+ 40% higher rate of fire.

With Y.V's passive that makes 60% higher rate of fire for all weapons (weapons have 40% of their regular reload time).

It also affects how fast a weapon reloads after using Y.V's active ability. After using Pop Pop the weapon will have 80% of its regular reload time. With Throne Butt that's 120%.

Sends you to Y.V's Crib.


Back 2 Bizniz

YV Ultra 2

Pop Pop will fire off 50% extra trigger pulls that won't consume ammo and won't affect the reload time. Which means a total of 3 trigger pulls with a cost of 2 and 160% of the weapon's regular reload time.

With Throne Butt, Pop Pop will fire a total of 6 trigger pulls with a cost of 4 and 240% reload time.

Sends you to Y.V's Crib.

Steroids icon1



Steroids A
Steroids Ultra 1
Medium Weapon Chests
Regular Weapon Chests and Cursed Weapon Chests increase in size and drop two of the same weapons.

Large Weapon Chests drop four random weapons instead of three.


Get Loaded

Steroids B
Steroids Ultra 2
Medium Ammo Chest
Regular Ammo Chests increase in size and have 10 Mini Ammo Chests inside, giving two for each type (bullet, shell, bolt, explosive and energy).
Robot icon1


Refined Taste

Robot A
Robot Ultra 1

Only higher tier weapons will drop from Weapon Chests and enemies. Meaning that Robot won't find weapons which normally (without Robot's passive) start dropping from chests in area 3-1 and below (check the Weapon Chest drops table).

Any weapons left behind when leaving a level will be automatically eaten.



Robot B
Robot Ultra 2

43% chance to burp out a random stationary pickup (Ammo Chest, Weapon Chest, Medkit or a Radiation Canister) after eating a weapon. Pickups will spawn on top of Robot and instantly open.

Ammo Chests have a chance to spawn as I.D.P.D. Chests. Weapon Chests can spawn as Cursed Weapon Chests if you have a Crown.

Any weapons left behind when leaving a level will be automatically eaten.

Chicken icon2


Harder to kill

Chicken A
Chicken Ultra 1

Each enemy killed by Chicken adds 1 second to the time she can survive while headless. The timer won't go above 5 seconds.



Chicken B
Chicken Ultra 2

Thrown weapons teleport to your secondary weapon slot after being thrown. Weapons thrown inside a portal are not affected.

Rebel icon1


Personal Guard

Rebel A
Rebel Ultra 1

Rebel starts each level with two allies. All allies will also have 30 HP instead of 12, which in addition lengthens their lifespan.



Rebel B
Rebel Ultra 2
Every time Rebel uses her active, she spawns two allies instead of one. Each spawn will cost 2HP.
Horror icon1



Horror A
Horror Ultra 1

Enemies that normally drop rads and Rad Canisters explode into radiation beam pellets upon death/when destroyed. The projectiles shoot out in all directions and otherwise act like parts of Horror's radiation beam dealing 1 damage each. Exploding doesn't reduce the amount of rads they will drop.

The amount of beam pellets each enemy/Rad Canister explodes into is 60% of the amount of rads it drops. That includes radiation added from other Horror's beam pellets hitting the enemy before it dies.

Enemies that don't drop rads (like the I.D.P.D. or Small Green Rats) and Destructible Objects are not affected by this mutation, unless they are hit with Horror's beam pellets.



Horror B
Horror Ultra 2

Level ending portals appear slightly before you have killed all enemies in that level. The portal opens when their combined health is equal or below 140. All remaining enemies are killed in the process.



Horror C
Horror Ultra 3

Doubles your Radiation capacity, increasing the amount of rads Horror can use for its active ability and Ultra Weapons.

Rogue icon2


Super Portal Strike

Rogue A
Rogue Ultra 1
Portal Strike UI Ultra
Doubles Portal Strike ammo capacity.

Portal Strike Ammo Canisters will give two ammo instead of one.


Super Blast Armor

Rogue B
Rogue Ultra 2

Upgrades Blast Armor. When Rogue gets hit, it creates four individual explosions in a triangular formation.


Character Ultra Mutation Icon Description
Skelly Icon



Skeleton A

Turns Skeleton back into Melting. Every mutation you picked while playing as Skeleton will be removed. You'll be able to pick nine new ones (standard eight and one extra) and one of Melting's ultra mutations instead.

Melting will have base 2 HP as opposed to Skeleton's 4 HP.



Skelly B
Firing a weapon with Blood Gamble will reduce that weapon's reload time by 80%. This only affects the current reload; it is not a permanent reduction.
Frog Icon



Frog A
Frog Ultra 2

Causes rads dropped by enemies and Radiation Canisters to emit toxic gas. Each Rad has a 1/3 chance to create one toxic gas cloud. Radiation Chunks are guaranteed to create 4 toxic clouds.



Frog B
Frog Ultra 1
Frog continuously spreads toxic gas as it moves.

This also affects Frog's active ability, which instead of charging a big cloud of gas, will release it as you hold down the button.


Co-op Ultra Mutations tableEdit

Going over level 9 when playing in Co-op and essentially reaching level 10 (Level Ultra) allows you to choose an Ultra Mutation unique to Co-op which will affect both characters. You will pick it instead of the character-specific Ultra Mutations listed above, which are unavailable in Co-op.

Mutation Description
Blood Bond

Blood Bond

Health pickups are shared. Picking up a Mini Medkit will restore 2 HP of both players simultaneously.

Gun Bond

Gun Bond

Ammo pickups are shared. Picking up a Mini Ammo Chest/Cursed Mini Ammo Chest will give its full amount of ammo to both players simultaneously.