Complex sentence: Bruce no longer finds an reason to kill the chamberman, because it was the system that was responsible for the deaths of his parents and vows to bring it down once and for all, no matter how long it will take.
Split into simpler sentences: Bruce no longer finds an reason to kill the chamberman, because it was the system that was responsible for the deaths of his parents. He vows to bring it down once and for all, no matter how long it will take.