The Skill hench pool is by far the strongest of the 6. Once you get him max sig, he basically works like nick fury where you have a 100% to get a second life. He also applies permanent bleeds from his specials but mostly his sp1 that remain for the rest of the match without a limit.
It sucks we only get a 2 star version of the champ, a 6 or 7 star would be pretty op for long fights with those permanent bleeds melting the opponent with no limit and the second life as a survival kit to tank sp3.
