We all know that Sabo is presumed dead. I never really thought much about it but my little bro was gettin way into Naruto so i made him read One Piece. And he brought up a possibility he could still be alive. If he was tough enough to hang with Luffy and Ace he might have taken a cannonball to the face and survived. The theory is that Killer is Sabo. Seein as how they both have blonde hair and Killer wears a mask it is completely possible. He could have survived with severe damage to his face which is why he wears the mask and he may not be able to talk as well. Anyone can see i got too much time on my hands. Well let me know what you guys think.