With the release of Kobolds and Catacombs Priest got a spell called Unidentified Elixir.
This card gives a minion +2/+2 and adds a bonus effect to your hand.
These bonus effects are as follows:
The card gives you some options to react to the board state and make a choice that’s going to give you the best play.
While giving a minion +2/+2 you can also give them a Divine Shield, summon a 1/1 copy, give it Lifesteal, or the Deathrattle to return the minion to your hand.