Glumshanks isn't particularly evil, just loyal to Kaos, who is evil. Despite Kaos's constant mistreatment of him, Glumshanks has always been loyal and faithful to Kaos. He is taller, more sensible, physically stronger and arguably smarter than Kaos, but serves him anyway. After The Darkness manipulates Kaos into firing him, Glumshanks helps the Skylanders for a time, even sacrificing himself to help them escape from Kaos's Sky Eater. After being rescued from Pandergast by the Skylanders, Glumshanks helps them until the end of the game, when, after The Darkness is supposedly defeated, he happily rejoins Kaos's side.