It's a character flaw, I know, but I'm not a fan of rivalry dynamics, so it would be safest for YC to be the brains to Rahn's brawn. Though if you'd like to play a character who is accustomed to being the biggest badass and has to deal with the fact that Rahn is an even bigger badass, that would be okay. (They could also have the brains / skills / magic /whatever.)
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