Slade is pretty good at hand to hand combat and some would argue that he could even defeat Batman! In the past, he has defeated Batman, but that was before Batman got his GL Power Ring. With it at his side, not even Slade’s fire abilities would be enough to win this round. Batman takes another win with this round. Batman wins.
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Batman has never beaten Deathstroke. Infinite Crisis, Injustice and Arkham Origins don’t count. Deathstroke laid waste to Bruce several times in the canon DC reality. Plus, Slade is a meta human badass. He could be a perfect replacement for Batman. This fight is basically like pitting Inspector Gadget against Boba Fett. Never forget the name “Deathstroke”.
Batman can definitely take him if he needs too….he’s Batman! In pure hand to hand skills, I don’t think that anyone in DC can handle him. Deathstroke does have the edge since he’s superhuman, but Batman has a lot of tech. Plus, if we give Batman prep time……
Deathstroke is physically even, has deadlier weapons, better protection and is more willing to use lethal force. It’s like a battle between a medieval knight and hired man-at-arms; the knight may be fierce but the mercernary is just as professional and unbound by the code of chivalry.
Deathstroke does tend to beat Batman when they face off against each other as well. Batman will have a very hard time winning this round in close combat. He needs to really use his gadgets to the best of their abilities in order to win this one. I would give Batman the edge in pure martial arts even if the gap in strength and armor do end up taking most of that advantage away though.