Mulligans
General Mulligans
Northshire Cleric is always a good opener. If you're playing a class that can kill a 2 health minion right from the start (Rogue or Shaman) it's often best to wait until you can buff Lightwarden before playing it.
Priest
This is an Aggro deck using Priest’s reborn synergies. I haven’t seen anything quite like it, but it’s worked pretty well.
When you begin, you want to create immediate pressure with Lightwarden . If you can play Extra Arms on her, she becomes harder to clear and you can begin to snowball her attack.
Injured Tol'vir is also a good opener. He can give you a heal target to activate Northshire Cleric, or to buff the Lightwarden.
In the mid-game, Psychopomp can revive these early minions with Reborn, making them continual threats. Usually one of them will have died by turn 4, so you can play Psychopomp on curve.
Wasteland Assassin threatens continued damage. It makes a good buff target, as well, because the opponent can’t clear it directly.
Note that Power Word: Replicate replicates the Reborn of a minion as well, so you can have a 5/5 Stealth with Reborn, or a 5/5 Lightwarden.
The finishing move is Leeroy Jenkins plus Wretched Reclaimer for 12 charge damage. If you can save Embalming Ritual for the combo, it adds up to 18 from hand.