Dethy decided that, in the event that he got evicted from his house, whoever moved in was in for a festival of firearms. As a last-ditch revenge plot against his family, he rigged more than a dozen shotguns all over his house: a crate of beer that would trigger a shotgun when enough bottles were removed, a trunk full of money in the attic rigged to blow your head off, the television had a shotgun rigged to it and even the water tank had more shotgun.
"This'll teach them to get cheated on by me! Haw!"
He wrote out a series of codes and riddles to help him remember where the shotguns were hidden, because he was clever; but he forgot to consult them and eventually shot himself in the head, because he's retarded.