Mulligans
General Mulligans
If you don't get Prince Keleseth this deck is weak af. Thankfully warlock has plenty of draw through the hero power, Imp, Runic Egg, and Meatwagon actually pulls Runic Egg and Devilsaur Egg from your deck hence drawing them.
The best way to utilize Meat Wagon that I could come with was in a Barnes deck. This deck attempts to Utilize the Prince Keleseth mechanic while still constantly applying pressure through a large amount of 1 drops. Barnes can pick up Arfus, Meat Wagon, Runic Egg, Possessed Villager. and Devilsaur Egg for a solid deathrattle.