I never understood why NOW he decided he had to kill his brother but I think the point was that he was motivated by revenge and that shit doesn't end well for anyone. He died trying to kill something that was already dead. He mainly served as a warning to Arya.

I wouldn't delve too deeply in the rules of his Frankenstein-ness. It's all magic. That sort of logic is out the window when we see a sword go through his brain.


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"Everyone has a plan until you punch them in the face. Then they don't have a plan anymore." (c) Mike Tyson

"what's a leader if he isn't reluctant"