Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Vampiric Link

Enchant creature
Whenever enchanted creature deals damage, you gain that much life.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Big Game Hunter

When Big Game Hunter enters, destroy target creature with power 4 or greater. It can't be regenerated.
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.)

Damnable Pact

Target player draws X cards and loses X life.

Swamp

Siege-Gang Commander

When Siege-Gang Commander enters, create three 1/1 red Goblin creature tokens.
{1}{R}, Sacrifice a Goblin: Siege-Gang Commander deals 2 damage to any target.

Shock

Sea Gate Wreckage

{T}: Add {C}. ({C} represents colorless mana.)
{2}{C}, {T}: Draw a card. Activate only if you have no cards in hand.

Damnation

Destroy all creatures. They can't be regenerated.

Mountain

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Ravenous Rats

When Ravenous Rats enters, target opponent discards a card.

Gone

Return target creature you don't control to its owner's hand.

Dead

Dead // Gone

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have Kederekt Parasite deal 1 damage to that player.

Scepter of Fugue

{1}{B}, {T}: Target player discards a card. Activate only during your turn.

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

Mogg Fanatic

Sacrifice Mogg Fanatic: It deals 1 damage to any target.

Distress

Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Kolaghan's Command

Choose two —
• Return target creature card from your graveyard to your hand.
• Target player discards a card.
• Destroy target artifact.
• Kolaghan's Command deals 2 damage to any target.