Abathur, Evolution Master

{b}{g},{t}: Sacrifice a creature then return that creature to the battlefield tapped. Its a Zerg in addition to its other types.

At the beginning of your end step, if a creature with First strike died this turn, Zerg you control gain First strike. The same is true for: Deathtouch, Double strike, Flying, Lifelink, Menace, Reach, Trample and Vigilance

"Assimilate essence."