For me I think it's probably Rafael Mendes at Pans 2012, Marcelo at ADCC 2011, Rodolfo at the 2011 Mundials or Roger Gracie at 2005 ADCC. Rafael at the Pans was ridiculous; completely on fire and would I be right in saying that no one scored a point on him? He capped off with a beautiful armbar on Cobrinha. Marcelo at ADCC 2011, submitting every one besides Kron and managing to guillotine Victor Estima in 30 seconds was ridiculous. Rodolfo's piece de resistance for me, showed his ridiculous ability and took both his weight and absolute. Roger submits all of his opponents in both weight and absolute on the biggest grappling stage. What more could you ask from him?