Hearthpwn

Win condition; 

Spiritsinger Umbra  +  Dreadsteed on empty board = 6 Dreadsteed instantly

Some Hints;

Against the Mage, Shaman and Priest don't play your  Dreadsteed without Spiritsinger Umbra because of Hex Polymorph Entomb Cabal Shadow Priest Card Name Shadow Madness Potion of Madness,

After combo, kill your Spiritsinger Umbra  as soon as possible because you have only 1 open slot for rest of the game,

Use that slot wisely, if your health is low and you have reno, don't fill it with another minion,

You can use Knife Juggler and Dreadsteed for efficient board clear,

You can use Ravenous Pterrordax on a Dreadsteed without a drawback,

Ravenous Pterrordax replaceable with Siphon Soul, I'm still testing it,

6 x Dreadsteed + Mal'Ganis for 18 damage combo.