From Under the Floorboards (SOI)

Madness {X}{B}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Create three tapped 2/2 black Zombie creature tokens and you gain 3 life. If this spell’s madness cost was paid, instead create X of those tokens and you gain X life.