If he does, does an 'effective' kill/knock out still count as a win?
Because, seriously, it doesn't matter how Voldemort spends his prep time, I very much doubt any magic he has is strong enough to withstand a trillion-ton-strength-superluminal punch. .
Superman hands down. Lord Voldemort may be the most powerful wizard, but he's still human. He still has limitations, like his reflexes would be slower than a speeding bullet maybe ? It's like "Avada---oh your behind me....well this is rather inconvenient..." then he gets his wand broken in two and head bashed in. I say he wouldn't last more than 30 seconds.
Nah, you can only come back so many times. It's like a mulligan in magic. You never get 7 cards after you mulligan. It's 6, then 5 if you do it again, then 4, 3, 2, 1 and then you stop at one. And then your pretty much useless.
Let's look at it this way. He died and came back something less than human. Close to it, but no cigar. So he dies again. He comes back something less of something less than human. And it keeps adding and adding and adding until he something so far from human he would require his own magic to keep him alive perpetually and I wouldn't think he would be that powerful of a wizard.
The only difference between a human and a wizard is magic. They still hold the same anatomical structures and same limitations (without the use of magic). Therefore, if no super villian being (let alone a human) could ever defeat Superman I doubt half of a human or even a full wizard could.