Mulligans
General Mulligans
Ideally, Ancestral Knowledge to get cards in your hand early before threats are out, Lightning Bolt to take care of an early nuisance creature, and Feral Spirit for some early blockers.
You generally want to save your Lava Shock for when you cast Elemental Destruction, but sometimes you gotta do what you gotta do.
Aggro Mulligans
These cards will help you whittle down those nasty little critters.Midrange Mulligans
The race is to get ahead of Midrange and get to your home run hitters to out-Midrange your opponent.Combo Mulligans
You'll want to go face and hope to wipe out Mr. Combo before he one shots you.
Control Mulligans
You're gonna want to go straight to the dome and quick. Control is going to do the same. Hopefully, your Healing Wave help you outlast the fight.
So, the hope here is to keep board control until you can get your Arcane Giants and Ragnaros on the board and beat down with Evolved Doppelgangsters and call on Yogg when the fight seems hopeless.