Bulba4 - An outfit you say? Why, it would be a lime green tuxedo with a matching bowler hat with a black trim. I'd also have a cane with a miniature strobe light at its head. I'd also have a monocle and a cape.
DragoKnight - On the plus side, you could move to yet-to-be-banned New Zealand.
As for your question, I've had a fair few rivals over the past few years. Mike (better known as TMM) was someone I absolutely loathed (and the feeling was more than mutual) up until a couple of years ago, when we became the Misc Marauders and generally went around dicking all over the forums. Tainted and myself also had a tense relationship that turned to friendship, but the bitterness we had for each other was not to the same degree as Mike.
Raz and I have never really been on bad terms, but we have often been on opposite sides of debates, and we have been vying for the title of the best user on the forum. It was never a rivalry as such, but friendly banter.
Dean and I used to hate each other, and perhaps he was the person I hated the most on the forums, but again, I came to be on good terms with him.
TheRustedOne was perhaps the greatest debating rival I had. For some reason, we always used to be on opposite sides of a debate, and he always won debates by attrition instead of reason, leading to heated debates that went round in circles.
I'd guess I'd go for Mike as my biggest rival, but he is one of the few users here who I do respect (even though he is banned).
DarkestLight - I had to check your question twice just to make sure you were some sort of Klansman. But the answer is no, as I've never liked the Resident Evil games.