Regeneration

 is a physical mutation which improves the player’s natural HP regeneration rate and allows the player to regrow lost limbs. This regeneration rate is applied in addition to the creature's normal HP regeneration rate.

Regeneration provides the ability to regrow missing body parts, with a level-based chance of occurring each turn. If the limb regeneration chance equals or exceeds 100%, the creature will be guaranteed to regrow a limb within one turn and, additionally, will be immune to decapitation. Note that only one limb can be regrown at a time, and parent limbs must be regrown before child limbs can be regrown (such as an arm needing to be regrown before a hand can then regrow).

Regeneration and other regeneration causing items also have the ability to remove removable minor physical debuffs that affect metabolic, respiratory, circulatory, structural, or neurological functioning, with a level-based chance to do so each turn. This includes Bleeding and Itchy skin; however, Regeneration cannot cure Fungal Infections that have already developed at any level because it is no longer considered an effect.

At mutation level 5, this ability extends to major physical debuffs, including diseases (such as Glotrot, Ironshank, and Monochrome) and their onset conditions (Sore throat, Stiff legs, and Blurry vision).

Formulas
The following formulas are used to determine healing rate, bonus, change to regenerate limbs, and chance to remove debuffs (rounded down) based on mutation level.

Effects affected
A non-exhaustive list of effects that can be removed by regeneration. These effects are only healed if they are applied to the creature that has regeneration, not their equipment. This includes natural equipment that is technically part of a creature's body, such as a.

Advantages

 * Gives the player easy access to limb regeneration, which normally requires specific resources, such as, , or
 * No limit on how many limbs a player can regenerate
 * Increases the player’s passive HP regeneration
 * Provides essentially full immunity to diseases at mutation level 5
 * Provides immunity to decapitation at mutation level 10
 * Provides essentially full immunity to fungal infections at mutation level 1

Disadvantages

 * High Mutation Point cost at character generation
 * The bonus to passive HP regeneration is too low to make a significant difference in most fights
 * Limbs are dismembered very infrequently in, and the “normal” methods of regenerating limbs are common enough to regrow any lost limbs
 * are easily found in, so a source of limb regeneration is always available if the player has a recoiler
 * This mutation may lock you out of getting fungal infections, preventing you from gaining any benefits they bring