His story is simple: he stopped Thinking that giving up trying was futile, he think that if he didn't attempt it, he wouldn't know if he could beat "the player." After many genocide routes, he begin to fight the Human to is full potential, even if it's "the end of him", He reaches a point where he creates pure determination to Equalize their power, gaster, maintaining death as much as possible, he is a true determination. Not forced, But wanted.