Red Lizards are the most dangerous species of Lizard (Rain World) generally encountered in Rain World, being eclipsed only by Train Lizards, which only appear for Inv (Rain World), and only in one region.
Red Lizards have a red head, a black body, and a very long black tail. Red spines run down their back and tail, forming a sort of crest. They may have additional red spines that run down either side.
They are the fastest lizard in the base game (despite also being the second heaviest), can see and hear from well off screen, and are incredibly aggressive, immediately attacking most other creatures, including other Red Lizards.