d100

Mutation

01-02

A new eye appears on your face, located at the center of your forehead. You now have advantage on Perception checks based on sight.

03-04

You gain a set of gills, becoming amphibious. Your hands and feet also become webbed, granting you a swimming speed equal to your walking speed.

05-06

Your skin secretes a slimy substance, giving you advantage on Strength and Dexterity checks when escaping the Grappled condition. However, creatures you are grappling have advantage on Strength and Dexterity checks to escape the Grappled condition. Additionally, if you have any hair, it immediately falls out.

07-08

A long skin membrane connects the tissue from your arm to your body. When you fall at least 10 feet above the ground, you can extend your skin membranes to glide horizontally a number of feet equal to your walking speed and take 0 fall damage.

09-10

A third arm grows out of your back. This extra arm can manipulate an object, open or close a door or container, pick up or set down a Tiny object, or wield a weapon that has the Light property

11-12

You grow a large, curled set of horns, much like that of a ram. If you move in a straight line of at least 15 feet towards a creature, you can use a bonus action to force them to make a Strength saving throw versus a DC saving throw of 8+your proficiency bonus+your Strength modifier. If they fail, they take 1d8 bludgeoning damage and are knocked prone. If they succeed, they avoid the damage and are not knocked prone.

13-14

Your tongue grows in length within your body and now secretes a sticky mucus. You now have the ability to, as an action, extend your tongue to a reach of 30 feet to retrieve a small object such as a key or a journal. You can also use the tongue to attempt to grapple a creature of Tiny size, forcing them to make a Strength or Dexterity saving throw versus a DC saving throw of 8+your proficiency bonus+your Dexterity modifier.

15-16

Roll a 1d2. On a 1, your arms grow in length, granting you an extra 5 feet in reach. On a 2, your legs grow in length, granting you a 5 foot increase in your movement speed and allowing creatures Small size or smaller to move through your space and not be considered difficult terrain.

17-18

Your eyes merge at the center of your head, becoming one large eye. You have advantage on Perception and Investigation checks involving sight, however, you have disadvantage on saving throws against effects that give you the Blinded condition.

19-20

Your skin becomes leathery and thick, gaining a resistance to fire damage.

21-22

Sharp blades protrude from your arms, acting like makeshift weapons. These count as natural weapons for you, utilize your Strength modifier for attack and defense rolls, and deal 1d8+STR modifier slashing damage on a hit.

23-24

Your ears disappear, with any and all ear openings closing completely. You gain the Deafened condition and cannot remove this condition unless you use the Greater Restoration spell to remove the mutation.

25-26

Your skin becomes hardened, gaining a +1 to your AC.

27-28

Your nose grows to a length that encompasses your entire face. You are permanently bonded and cannot speak. However, you gain advantage on all skill checks involving smell.

29-30

You grow a turtle shell that covers your body. As an action, you can withdraw into the shell, gaining a +4 on your AC and giving you advantage on Constitution saving throws. However, while inside the shell, your speed is reduced to 0, you cannot take reactions, and you have disadvantage on all Dexterity checks and saving throws. You can use a bonus action to emerge from the shell.

31-32

The bottom part of your jaw elongates to abnormally large proportions. You have difficulty speaking and will need to make a Performance check equal to your Spellcasting modifier if you wish to cast a spell utilizing verbal components. If you fail the check, you are unable to cast the spell.

33-34

You grow a large reptilian tail. If you are hit by an attack, you can use a reaction to detach your tail and have it take the damage, completely avoiding the attack. The tail regrows after a long rest.

35-36

Your skin becomes bloated becoming vulnerable to piercing damage

37-38

Your legs decrease in size, becoming smaller and stubbier. You incur a 5 foot penalty in your speed.

39-40

Chameleon-like scales grow over your skin. Once per long rest, you can cast the Invisibility spell. Wisdom is your spellcasting ability for this spell.

41-42

You grow a second head. This head has its own personality but doesn’t say anything particularly interesting or useful. The second head also cannot use verbal components for spells.

43-44

Your body becomes resilient to other toxic substances, granting you resistance to poison damage and gaining advantage against the Poisoned condition.

45-46

Your head doubles in size. You have disadvantage on saving throws against being knocked prone.

47-48

Your skin becomes brittle becoming vulnerable to bludgeoning damage.

49-50

A pair of bat-like wings grow from your back, granting you a flying speed equal to your walking speed.

51-52

Your eyes gain the ability to shoot out concussive blasts. As an action, you can make a ranged attack roll using your Constitution modifier for your attack roll to shoot out a set of energy rays with a range of 60 feet. On a hit, the target takes 1d8 force damage and must make a DC12 Strength saving throw or be knocked prone.

53-54

Feathers grow all across your body except for your eyes, mouth, nose, and other orifices. This doesn’t cause any additional effects, but they do feel soft.

55-56

You gain the ability to better communicate with wildlife. You have advantage on Animal Handling checks and you can cast the Speak with Animals spell that you can cast once per long rest. Wisdom is your spellcasting ability for the spell.

57-58

Your face becomes covered in zits and acne as your voice becomes cracked and prepubescent. You have disadvantage on all Charisma skill checks.

59-60

Your ears turn into bat ears and your hearing becomes even more perceptive. You gain blindsight up to a range of 30 feet. However, you become vulnerable to thunder damage.

61-62

Your skin becomes translucent, allowing anyone to view the inside of your body. You get disadvantage on Persuasion checks, but advantage on Intimidation checks.

63-64

Your leg muscles become springy and strong. Your jump distance is doubled.

65-66

A large growth begins to grow on your body. After 1 day, this growth will grow and separate from your body, growing into a miniature version of yourself. This creature becomes immediately hostile towards you. The DM may use the zombie statblock when running the miniature version of yourself.

67-68

You grow a beard if you do not have one. If you do have a beard, it grows thicker and longer.

69-70

A set of porcupine quills grow out of your skin. If a creature makes a melee attack against you, they take 1d4 piercing damage.

71-72

Your skin becomes pliable and you can mold it as you see fit. You can cast the Alter Self spell once per long rest. Wisdom is your spellcasting ability for this spell.

73-74

Your fingers become elongated, rubbery, and floppy. You can no longer hold onto objects or weapons.

75-76

Your body feels cold and the air around you is chilled. Once per long rest, you can cast the spell Armor of Agathys without any material components, as you can use the water molecules around you as icy armor. Wisdom is your spellcasting ability for this spell.

77-78

Your teeth become abnormally large, and become strong enough to crush wood, stone, and other teeth.

79-80

Your mind pulsates with minor psionic abilities. You can speak telepathically to any creature within 30 feet of you. Your telepathic utterances are in a language you know and the creature understands you as long as it knows that language. Your communication does not give the creature the ability to respond back telepathically.

81-82

Your neck becomes one foot longer.

83-84

Your lungs become larger and more sturdy. You can hold your breath for up to 1 hour.

85-86

A putrid stench comes off of you. Any creature within 10 feet of you must make a DC13 Constitution saving throw. If they fail, they spend their action and their bonus action retching and heaving.

87-88

You gain bioluminescent skin. You can cast the Light cantrip, causing your skin to light up. Wisdom is your spellcasting ability for this spell.

89-90

Your bones become gelatinous and amorphous, allowing you to squeeze through spaces as narrow as 1 foot wide, provided you are not wearing any armor and are not carrying any objects.

91-92

Your left ear is now where your right eye used to be. Your right eye is now where your nose used to be. Your nose is now where your right ear used to be. Your right ear is now where your mouth used to be. Your mouth is now where your left eye used to be. Your left eye is now where your left ear used to be.

93-94

Spiky hairs come out of your palms and your feet, granting you a climbing speed equal to your walking speed.

95-96

One of your arms is replaced with an octopus-like tentacle. When you make an unarmed strike with this tentacle to grapple a creature, the target immediately becomes grappled by you, no save required. The target has disadvantage on saving throws to escape the grappled condition.

97-98

Your body radiates with radioactive energy. Any creature within 5 feet of you must make a DC 15 Constitution saving throw, taking 1d8 acid damage on a failed save and half as much on a successful save. 

99-00

You gain self-healing abilities when your body is pushed to its limits. At the end of each round, provided you have half of your health or less and are not incapacitated or dead, you regain 1d4 hit points.