Has this ever happen? This would be an epic battle. Both basically trained to be the consummate warrior. Diana does have divinity to her advantage (meaning that her powers were bestowed to by the gods,) but Barda has a height advantage, and I imagine that Barda would be a bit more ruthless.
I have to give the edge to Diana because of "speed of Hermes," factor, the fact that she can fly, and her reflexes are faster.
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