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.
2012-10-01
If Izzet Keyrune becomes a creature in a way other than its own activated ability, its last ability will still work.
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: Until end of turn, this artifact becomes a 2/1 blue and red Elemental artifact creature.
Whenever this artifact deals combat damage to a player, you may draw a card. If you do, discard a card.
Until the ability that turns the Keyrune into a creature resolves, the Keyrune is colorless.
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