Although it's Ron Gilbert's adventure game legacy that you see in the dialogue trees and the fetch quests, and the tiniest, most primitive shard of Diablo's design shines through in the looting, I like to think that the secret influence on DeathSpank has always been Sergio Aragones.
The Spanish cartoonist has a real legacy at places like Mad Magazine, where he's helped to forge a rich bloodline of brave and idiotic heroes. Like DeathSpank, they have long, bendy legs and barrel bodies, and their faces are contorted with moronic concentration. Like DeathSpank, they spend a lot of time getting things wrong in the name of doing things right.
Mad Magazine's snarky strain of anarchy flows right through the DeathSpank games, in fact, whether the hero's collecting magical underpants or piecing together a dangerously hot Taco to placate a stubborn villager. In The Baconing, the latest instalment, he's burning the fabled Thongs of Virtue one by one in order to defeat a dangerous AntiSpank he accidentally brought to life.