My top three would be:

Rilla
Rilla
Rilla

Or rather

Skallagrim: I don't think I've ever beaten him in a straight up fight. Ever.

Melonhead: He's actually pretty good, even compared to me, and I've been fighting basically since the start of my RP career.

DJ: I get the feeling DJ, while good now, is actually much better than he lets on, based off him being around the likes of Skally, and Saladin.

Honorable bitchin': Khan, mainly due to characters, a lot of them seem like -bosses- of given level, rather than actual character.