Lineage System

Rain World has a not very well known system called the Lineage System. When you kill a creature in the world, after a number of cycles it will eventually respawn. However, it won't always respawn as the exact same creature... certain rooms in each region have specially defined rules that dictate which creatures are eligible to be the reincarnated offspring of the killed creature, and the respective probabilities. This is the only way you can encounter a red lizard.