I say Xena would win, but under some conditions:
1) She'd have to find a way to end it quickly, otherwise Herc would win simply by wearing her out. His godly heritage does enable him to keep on fighting longer than her.
2) She wouldn't be able to just straight duke it out, she'd have to use some form of trickery, a distraction, something, otherwise his shear strength would get her. I mean, seriously, he's strong enough that one good blow to the head and it's lights out.
As for why, to me, it comes down to the fact that she has been to the dark side, faced her demons, and when she found the light, IMO, she came out stronger. Herc's not a complete dummy, and he's got all that demi-god strength and stamina, but she does have him beat (again, IMO) in brainpower and sheer tenaciousness. Once she really sets her mind to something, she doesn't give up, and because she does have a dark side, she's better able to come up with tricks, to find ways to take people off guard or just plain mess with their heads, while Herc is inherently good one, and really, deceiving people, even in battle, is not in his nature.
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Of course, Bellepheron didn't have as much chest hair as Hercules. Hmmm.











