Cycle: Keyrunes

Each guild has a Keyrune, an artifact that taps for mana of either of that guild’s colors and can become a creature.



Golgari Keyrune
3 Mana
Artifact
Tap: Add Black Mana or Green Mana to your mana pool.
Black ManaGreen Mana: Golgari Keyrune becomes a 2/2 black and green Insect artifact creature with deathtouch until end of turn.


Until the ability that turns the Keyrune into a creature resolves, the Keyrune is colorless.

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. For example, say you activate the last ability of Golgari Keyrune. After it resolves, you cast Giant Growth targeting it. It’s now 5/5. Then Diminish (“Target creature becomes 1/1 until end of turn”) is cast targeting it. Once Diminish resolves, Golgari Keyrune would be 4/4. Activating Golgari Keyrune’s last ability a second time would make it 5/5 again until end of turn.