I mean, this is obvious when you consider you intentionally kill the Guide by burning him alive through a voodoo doll to summon the Wall of Flesh. It even says "You are a terrible person" in the tooltip. The whole game is basically you killing bad guys in order to unleash WORSE guys so you can kill them too, and unleash EVEN WORSE guys just for the pleasure of also ending them."Within each world is a Guardian who serves as the worlds master and core. Once this creature is destroyed the world will release the ancient spirits of light and dark to expedite the process of finding a new guardian."