Board Thread:General Discussion/@comment-10452902-20170507091901

One of the most famous things in the game is that the player/Frisk can spare Sans about halfway through the battle but if they do so, then they get killed instantly regardless of how much health they have left. But this very act of revenge instead of accepting it ultimately dooms the Frisk to destroying the world when they otherwise would not have. Sparing Sans means the player and thus Frisk is giving up their genocidal way, they can't bare to kill Sans and thus, their Humanity has become dominant over their demonic lust to destroy the world. If Sans were to accept it, then after a breif chat, Frisk would reset and redo the pacifist route, saving their soul. While yes, killing so many people have tainted their soul so greatly, it would almost purify it and at least Frisk would still have a soul. Although in the context of this world, we don't entirely know the ramifications of giving up your soul, it is safe to say that doing so forever leaves Frisk not a Human but a demon unable to find true peace. It leaves Frisk, no matter how pacifist they become worst than Chara and Omega Flowey put together and at risk of relapsing into Frisk's old ways because without a soul, Frisk cannot truly change. 