Ex-Mutants is set in a post-apocalyptic world where mutant creatures have taken over. You play as one of the few remaining humans who possess the knowledge to restore humanity. Your mission is to rescue your fellow human comrades from the clutches of the evil mutant Lord Sluggo, while also searching for six genetically pure samples to help rebuild society.
The gameplay involves navigating through 11 levels of the desolate wasteland known as Sluggtown, fighting against hordes of mutants and avoiding deadly traps. Armed with a trusty battle axe, you must hack your way through levels, using your wits and combat skills to overcome obstacles and defeat enemies.