Most powerful version? Pre-Crisis KK then. Hmm, he stomps, except... I'm not sure if someone invented an MA style that can counter the Bat-Kick (which dropped the Hulk in those days btw).
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I would say... the four win almost every time, a call that probably surprises a lot of you.
You see, while KK had a bunch of moves against Supers, when he fought other martial artists he did not dominate nearly as much. Even back in the 70s pre-crisis, Batman could give him a rumble.
So four top-tiers against him? While he's better than any of them individually, he can't really handle them in multiples.
I think more of an issue is that Val didn't really fight a lot of street level foes back in the day. When he did - Black Mace, Black Dragon - he generally took them down with relative ease, but even if he hadn't they were products of 30 century teachings, and therefore not comparable to guys like Batman, Captain America, etc.
If he's prepared, though, I think he could probably take it. Pre, Post, Zero Hour...there was always an element of preparedness to Val's efficacy. I recall, during Gail Simone's run, he was getting his clock cleaned by a literal army of super villain prisoners (literally the most dangerous scum in the universe) when he wasn't prepared, and then he gets a brief break, says he's had time to prepare, and defeats them all single handidly.
Batman never fought Val, Pre-Crisis. And when Val DID battle Bruce, Post Crisis, he nearly defeated him, if it wasn't for the fact that he just got out of a coma and Black Lightning interfering.
As for pre-crisis Val fighting MA's, he DID own Black Dragon and Black Mace, who was equivalent to Val.