Selvala, Eager Trailblazer (Promo Pack) [Outlaws of Thunder Junction Promos]

Vigilance

Whenever you cast a creature spell, create a 1/1 red Mercenary creature token with "T: Target creature you control gets +1/+0 until end of turn. Activate only as a sorcery."

T: Choose a color. Add one mana of that color for each different power among creatures you control.