Diamond Lion - mtg.wtf

Artifact Creature - Cat

, Discard your hand, Sacrifice Diamond Lion: Add three mana of any one color. Activate only as an instant.

"The merchant asked for riches no one had ever dreamed of. The djinn, smiling, granted his wish."
—Afari, Tales

2/2

2021-06-18 Even though you can only activate this as an instant, it is still a mana ability. It doesn't use the stack and cannot be responded to.
2021-06-18 You can't cast an instant (or activate an ability as an instant) while casting a spell. Therefore, much like Lion's Eye Diamond, you can't activate the ability intending to use the mana to cast a spell from your hand.

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