Simic Keyrune

Oracle Text

T: Add G or U.

GU: Simic Keyrune becomes a 2/3 green and blue Crab artifact creature with hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Card Rulings

4/15/2013 Until the ability that turns the Keyrune into a creature resolves, the Keyrune is colorless.
4/15/2013 Activating the ability that turns the Keyrune into a creature while it’s already a creature will override any effects that set its power and/or toughness to another number, but effects that modify power and/or toughness without directly setting them will still apply.

Additional Information