A guy I've been following since I saw him face Kron Gracie at brown belt in 2007, is Otavio Sousa.
If you follow my blog, that should come as no surprise.
It's amazing to go back and see a competitor 6 years ago, at brown belt, who is now 2x world champion.
Kron Gracie vs Otavio Sousa 2007 Pan Ams @ Brown Belt:
And here he is winning his 2nd consecutive world championship over the always dangerous Claudio Calasans in 2013 at the Mundials: