Gais gates doesn't leave him with any fatigue though, he can activate or deactivate it and suffer from no side effects unless pushed to 7th Gate.
No physical attack is going to hurt Orochimaru straight up, though Asa Kukaju can cause him mad damage and as flexible as oro is, he isn't dodging all those punches or flames.
Hirudora would simply obliterate him and if that doesn't work then ripping his neck from his body will.