Mister Gold and Mister Silver. Why would a seemingly random pair of (admittedly quite muscular) gay guys be such powerful fighters? A: Due to being lovers, they are completely in-sync with each other, and B: They know the male body inside and out.
How does selling moves work? Gene apparently buys cards with the technique on them so he learns them, but he can sell those cards back and be unable to use the move anymore... Maybe the tellers are siphoning his memory?