Discard Warlock
Blizzard has been attempting to get Discard Warlock off the ground for what feels like forever. To be fair, there was a Zoo version that had quite a few discard options that was pretty competitive. They are at it again in Rastakhan’s Rumble, and this time they mean business. There are four new discard based cards, and they seem to be pretty interesting at first glance.
The new mechanic that could make this all work is that two of the discard cards (Reckless Diretroll and Shriek) will discard the lowest Cost card in your hand. The other card that potentially brings this deck together is Soulwarden. Being able to add 3 cards back to your hand that you discard in the game is pretty powerful and will likely be a must include if this deck is to work.
The final new option is High Priestess Jeklik, and if you can get her going by getting some copies and some thrown onto the board, you might just survive the game long enough to get some of those discarded cards back!