Mirrodin's Core

Prevent all noncombat damage that would be dealt to you and creatures you control. Whenever a nontoken creature you control enters, create a 2/2 white Unicorn creature token.

When this creature enters, tap up to one target creature. You gain life equal to that creature's power.

(T: Add W.)

3: Exile another target creature you control, then return it to the battlefield under its owner's control. Whenever another creature you control enters, you may pay G/W. If you do, put a +1/+1 counter on it. If it's a Unicorn, put two +1/+1 counters on it instead. (G/W can be paid with either G or W.)

Create four 1/1 white Dog creature tokens.

Flying Whenever this creature attacks, other attacking creatures you control with flying get +2/+2 until end of turn.

Whenever this creature attacks, if you control an artifact or enchantment, this creature gets +1/+1 and gains lifelink until end of turn.

When this creature enters, put a +1/+1 counter on each other creature you control.