Blood-Toll Harpy

Flying
When Blood-Toll Harpy enters, each player loses 1 life.

Firespitter Whelp

Flying
Whenever you cast a noncreature or Dragon spell, Firespitter Whelp deals 1 damage to each opponent.

Rakdos Signet

Grab the Prize

As an additional cost to cast this spell, discard a card.
Draw two cards. If the discarded card wasn't a land card, Grab the Prize deals 2 damage to each opponent.

Sanguine Syphoner

Whenever this creature attacks, each opponent loses 1 life and you gain 1 life.

Sol Ring

Bond of Agony

As an additional cost to cast this spell, pay X life.
Each other player loses X life.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Caustic Hound

When Caustic Hound dies, each player loses 4 life.

Izzet Signet

Dimir Signet

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Circle of Affliction

As Circle of Affliction enters, choose a color.
Whenever a source of the chosen color deals damage to you, you may pay {1}. If you do, target player loses 1 life and you gain 1 life.

Kill! Maim! Burn!

Choose one or more —
• Destroy target artifact.
• Destroy target creature.
• Kill! Maim! Burn! deals 3 damage to target player.

Abaddon the Despoiler

Trample
Mark of Chaos Ascendant — During your turn, spells you cast from your hand with mana value X or less have cascade, where X is the total amount of life your opponents have lost this turn.