Canker Abomination [Ultimate Masters] SPA Draco desgarrado you may pay {0} rather

you may pay {0} rather than pay the mana cost for a spell you cast with converted mana cost X or less

Set: Chronicles Type: Instant Uncommon Cost: {1}{W} Creatures you control get +0/+2 until end of turn

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Set: Commander 2011 Type: Artifact Creature — Golem Rare Cost: {4} When Solemn Simulacrum enters the battlefield

but nothing holds back the heat of the suns

Canker Abomination [Ultimate Masters] SPA Draco desgarrado you may pay {0} ratherSet: Ultimate Masters Type: Creature ? Treefolk Horror Common Cost: {2}{B G}{B G} As Canker Abomination enters the battlefield, choose an opponent. Canker Abomination enters the battlefield with a 1 1 counter on it for each creature that player controls. Once the hideous disease takes hold, it spreads through both bark and mind.