So, I was thinking, what would happen if the three of the most efficient droids in Star Wars went against each other? It would be one entertaining battle, wouldn't it?
So, anyways, I'm going to say that HK-47 may be able to beat IG-88 if he went against one of them, but it would be a close battle, as IG seems to be equipped with a crazy amount of weaponry. If he went against all four IGs, HK would probably not win, just because of the amount of weaponry on the IGs and the fact that he's outnumbered (that's not to say he'd take one or two with him though
). However, as much as I love HK-47, I'm going to have to call the YVH droid on this one, simply because they have regenerating armor, and if I remember correctly, can even take a shot or two from a coralskipper. They've also been shown to be able to crush Vong armor with their bare hands, though I could be wrong.