Health

Every creature in Rain World, including the, has a health value (known in code as "resistance"). This value determines how much damage a creature can take before dying.

Most of the time, damage is dealt by s, and the damage dealt varies on many things, most noticeably which Slugcat is throwing it. The following are damage values for Slugcats on the game's different difficulties:
 * , and any starving Slugcat (except ) deals damage using this formula: 0.6+0.3*(x^4) x is a random number from 0 to 1, resulting in a possible damage range from 0.6 to 0.9.


 * and deal 1 damage per spear hit.


 * , and  deal 1.25 damage per spear hit.
 * deals 3 damage per spear hit, which is reduced to 0.3 when exhausted.

Although the damage difference is small between most Slugcats, the increased or decreased number of Spears that must be used to kill certain creatures can greatly change how the player must approach combat.

deal somewhere between 5 and 8 damage, though the exact amount has not yet been determined.

deals 0.01 damage, which is completely insignificant damage to most creatures.

s deal 0.85 damage, less than a normal Spear.

s deal ≈55.7 damage, able to kill a Leviathan in 18 hits.

The most powerful weapon in the game is the, which can kill anything instantly, with the sole exception being Iterators, who are affected by the gravity pull but not the explosion.

Creature Values
The following is a rough list of the health values of each creature in the game:

Calculating Health
The health of a creature is defined by the Base Damage Resistance value, which serves as the dividend in a calculation for determining damage. The Base Damage Resistance value is double the Toughness attribute of a Creature. Blue Lizards have a Toughness of 0.5 and a Base Damage Resistance value of 1, and Green Lizards with 2.5 Toughness have 5 Base Damage Resistance. In other words, a Blue Lizard has 1 HP (Health Pool/Hit Points), while a Green Lizard has 5 HP.

Stunning
The stun mechanic is closely related to damage, temporarily immobilizing a creature and preventing/reducing further retaliation. The Base Stun Resistance value for a creature determines the extent to which a creature is stunned, often deployed alongside normal damage when a creature is attacked. Different sources vary in the amount of 'stun damage' they inflict, with Explosives applying a heavy stun from their blast.

Damage Types
The Damage Resistances value of a creature serves as the dividend for calculating the damage received from the corresponding damage type. There exists a total 6 listed unique damage types: Blunt, Stab, Bite, Water, Explosion, and Electric. Within the code, these damage types are sometimes denoted using integers on a range of 0-5, where 0 = Blunt, 1 = Stab, 2 = Bite, 3 = Water, 4 = Explosion, and 5 = Electric.

By default, Lizards have a Bite Damage Resistance of 2.5, which is a multiplier of 40%, or a -60% reduction in damage. There are many creatures that have certain damage type resistances defined, either increasing or decreasing the actual damage resulting from the corresponding damage type.

For instance, both Brother and Daddy Long Legs are highly susceptible to the Explosive damage type, where they can be killed by a direct hit to their core with just a single Explosive Spear, even though Brother Long Legs have an HP of 100 and Daddy Long Legs have a HP of 200, far surpassing the normal damage output of a Spear's blast.

Other creatures like Centipedes have an Electric Damage Resistance, set at 102 for all Centipedes, and therefore take less than 1% of the normal damage.

Body Chunks
A creature is made up of one or more body chunks, which may be grouped up into subsections of the total creature; Lizards have a single head, throat, and body, while Centipedes have a series of body segments that are capped off with a head at each end, resulting in two heads and a variable number of body segments in between for all Centipede subspecies. These various body subsections often have different damage resistances and additional properties, but otherwise function together as a single cohesive unit with a shared health pool until the creature is exhaustively incapacitated, or dead. For Lizards, their throat subsection receives 150% of the base damage from a source, which increases damage dealt. Damage to their head has a multiplier of 10%, severely reducing damage.

For Centipedes, the amount of damage taken depends on if the hit body segment has a shell at the time of impact, providing a damage reduction, whereas a segment without a shell that is hit takes an increased amount of damage. There is a threshold at which the shell of a Centipede body segment breaks off, often taking 1 spear hit. The head segments of Centipedes take decreased damage if stabbed with a spear when the head already has another spear lodged within it.

Bleedout
Creatures enter a Bleedout state when their health reaches 0 or lower, having a chance to die every frame. For most creatuers, if health is below 0, then they have a (-health*2.5)% chance of dying each frame. If health is equal to 0, then there is a (-0*2.5)%=0% chance of dying each frame.