Cedric Phillips has been playing it on his twitch a lot in between matches on MTGO, and he's been winning a lot with it. Rancor makes that deck legitimate. Having a pump spell that is basically infinite except for unsummons, and makes it so your dude can't be chumped? That's insane.
By the way, did anyone catch the twitter controversy? Apparently in the finals, one of the guys from Puerto Rico, the one playing affinity in modern, looked VERY suspicious. Tom Martell livestreamed it and detailed how he was cheating and why he thinks he was cheating.
WHO THE FUCK CHEATS LIVE ON THE INTERNET? IN THE FINALS OF A LARGE EVENT?