Devan Shell

Devan Shell is an evil tortoise mastermind and the main villain of Jazz Jackrabbit - parodying the classic "tortoise and the hare" rivalry of old: however unlike the slow-and-steady tortoise of legend Devan is a crazed inventor who has began conquering entire worlds in his quest to rule the universe.

Devan suppresses the native life forms of every world he has conquered and kidnaps the Princess Eva Earlong of Carrotus out of rage after the planet successfully fends off his invasion: thus Jazz Jackrabbit is called in to rescue the princess and put a stop the Devan's insane war-machine.