What is FrankenCastle?
Well, I'm glad you asked. FrankenCastle is the awesome creation of Rick Remender. After Punisher was brutally killed by Daken, he was stitched back together by The League of Monsters, to fight Japanese monster hunters, ride dragons, kill ninjas, own Daken and generally just be awesome.
I'm going to skip posting his origin. You should do yourself a favour and read it.