Terminal Agony

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

Famished Foragers

When Famished Foragers enters, if an opponent lost life this turn, add {R}{R}{R}.
{2}{R}, Discard a card: Draw a card.

Olivia's Dragoon

Discard a card: Olivia's Dragoon gains flying until end of turn.

Kitchen Imp

Flying, haste
Madness {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.)

Cabal Initiate

Discard a card: Cabal Initiate gains lifelink until end of turn.
Threshold — Cabal Initiate gets +1/+2 as long as seven or more cards are in your graveyard.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Fiery Temper

Fiery Temper deals 3 damage to any target.
Madness {R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Alms of the Vein

Target opponent loses 3 life and you gain 3 life.
Madness {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.)

Dark Ritual

Epiphany Storm

Enchant creature
Enchanted creature has "{R}, {T}, Discard a card: Draw a card."

Skophos Reaver

During your turn, Skophos Reaver gets +2/+0.
Madness {1}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Axiom Engraver

Axiom Engraver enters with two oil counters on it.
{T}, Remove an oil counter from Axiom Engraver, Discard a card: Draw a card.

Funeral Rites

You draw two cards, lose 2 life, then mill two cards.

Skirge Familiar

Viashino Lashclaw

{T}, Discard a card: Creatures you control gain haste until end of turn.

Faithless Salvaging

Discard a card, then draw a card.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Hell Mongrel

Discard a card: Hell Mongrel gets +1/+1 until end of turn.
Madness {2}{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.)

Revolutionist

When Revolutionist enters, return target instant or sorcery card from your graveyard to your hand.
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Putrid Imp

Discard a card: Putrid Imp gains flying until end of turn.
Threshold — As long as seven or more cards are in your graveyard, Putrid Imp gets +1/+1 and can't block.

Twins of Maurer Estate

Madness {2}{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.)

Reckless Wurm

Trample
Madness {2}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Bloodmad Vampire

Whenever Bloodmad Vampire deals combat damage to a player, put a +1/+1 counter on it.
Madness {1}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Gorgon Recluse

Whenever Gorgon Recluse blocks or becomes blocked by a nonblack creature, destroy that creature at end of combat.
Madness {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.)

Psychotic Episode

Target player reveals their hand and the top card of their library. You choose a card revealed this way. That player puts the chosen card on the bottom of their library.
Madness {1}{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.)

Fodder Tosser

{T}, Discard a card: Fodder Tosser deals 2 damage to target player or planeswalker.

Swamp

Grave Scrabbler

Madness {1}{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.)
When Grave Scrabbler enters, if its madness cost was paid, you may return target creature card from a graveyard to its owner's hand.

Gilt-Blade Prowler

{1}, {T}, Pay 1 life: Draw a card. Activate only if you've discarded a card this turn.

Haggle

You may discard a card. If you do, draw a card. (Then exile this card. You may cast the creature later from exile.)

Merchant of the Vale

Merchant of the Vale // Haggle

Call to the Netherworld

Return target black creature card from your graveyard to your hand.
Madness {0} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Oblivion Crown

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature has "Discard a card: This creature gets +1/+1 until end of turn."