Sudden Corruption, Hero Malfunction

''It's even worse if the hero is a robot. ERR 404''

Just at the end of the Big Fight, the Hero wields their weapon, glares at the Villain, and slaughters them right on the spot. Very much unlike in Happy Ending, this turns out to be a bad thing as the Villain is to The "Villain" as Hero is to The "Hero". The Hero, err, the "Hero" was actually going after the Villain to obtain some weapon or power they held and they were using their allies as tools. Or something like that. Most of the time, someone snaps the Hero out of it and rescues them from the dark side before the Hero could do anything too evil.