Warren Warleader [Bloomburrow Prerelease Promos]

Offspring 2 (You may pay an additional 2 as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever you attack, choose one —
• Create a 1/1 white Rabbit creature token that's tapped and attacking.
• Attacking creatures you control get +1/+1 until the end of your turn.