From Under the Floorboards

Madness [Variable Colorless][B][B] (If you discard this card, discard it into exile. When you do, cast it for its madness cost/put it into your graveyard.)

Put three 2/2 black Zombie creature tokens onto the battlefield tapped and you gain 3 life. If From Under the Floorboards's madness cost was paid, instead put X of those tokens onto the battlefield tapped and you gain X life.