Tavern Swindler

{T}, Pay 3 life: Flip a coin. If you win the flip, you gain 6 life.

Night's Whisper

Crackle with Power

Crackle with Power deals five times X damage to each of up to X targets.

Fire Covenant

As an additional cost to cast this spell, pay X life.
Fire Covenant deals X damage divided as you choose among any number of target creatures.

Stormfist Crusader

Menace
At the beginning of your upkeep, each player draws a card and loses 1 life.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Keen Duelist

At the beginning of your upkeep, you and target opponent each reveal the top card of your library. You each lose life equal to the mana value of the card revealed by the other player. You each put the card you revealed into your hand.

Rowan, Scion of War

Menace
{T}: Spells you cast this turn that are black and/or red cost {X} less to cast, where X is the amount of life you lost this turn. Activate only as a sorcery.

Bitter Triumph

As an additional cost to cast this spell, discard a card or pay 3 life.
Destroy target creature or planeswalker.

Magus of the Mirror

{T}, Sacrifice this creature: Exchange life totals with target opponent. Activate only during your upkeep.