We know orochi is easy, hell he is the easiest boss ever but we are talking about Orochi's moves. If you are talking about A.I. then hell Everybody would beat Orochi.
Orochi. Heck, even story-wise, he's a reincarnated god!! No wonder he has a super that takes up the whole screen. I haven't played, or seen, KOF 2001 yet, but i'm pretty sure Igniz can't beat Orochi.
Orochi is a lazy dog (why expected that one reincarnated-god that sleep during 1800 years, run ... combo player.? and Ignis is your suprised big boss with great tecnics similar to the old school of the KOF bosses (I wait taht Ron is the boss of 2K1, but..).
My vote is for Ignis.