Shadow Madness + Young Brewmaster = yum. I was a little afraid it would return the creature I stole to his hand, because some crazy shit works that way, but nope. I took control of his Stampeding Kodo, used it to attack one of his own creatures and kill it, dropped a Brewmaster to return his damaged kodo to my hand, and then summoned it next turn to kill another one of his creatures instantly haha. 2 cards killed 3 of his creatures and left me with 2 fresh creatures on the board. 4 card advantage ftw, not to mention 2 decent creatures on the board.
Sylvanas isn't as good as she looks though. She's not that difficult to work around with only 5/5. You can easily set it up so she only gets a small shit creature. Ragnoros is amazing because the 8 damage is going to go off no matter what, and Ysera you get the dream card no matter what which is amazing and she's super hard to kill. I think Baron Geddon might be underrated, been playing him a lot in various decks since I got him, and with a little strategy and proper timing he can work in a lot of decks. Even if he dies quickly, you can still wipe a board.