Volcano Hellion

Volcano Hellion has echo {X}, where X is your life total. (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Volcano Hellion enters, it deals an amount of damage of your choice to you and target creature. The damage can't be prevented.

Boros Reckoner

Whenever Boros Reckoner is dealt damage, it deals that much damage to any target.
{R/W}: Boros Reckoner gains first strike until end of turn.

Acidic Soil

Acidic Soil deals damage to each player equal to the number of lands they control.

Crackling Doom

Crackling Doom deals 2 damage to each opponent. Each opponent sacrifices a creature with the greatest power among creatures that player controls.

Zurgo Helmsmasher

Haste
Zurgo Helmsmasher attacks each combat if able.
During your turn, Zurgo Helmsmasher has indestructible.
Whenever a creature dealt damage by Zurgo Helmsmasher this turn dies, put a +1/+1 counter on Zurgo Helmsmasher.

Stuffy Doll

Indestructible
As Stuffy Doll enters, choose a player.
Whenever Stuffy Doll is dealt damage, it deals that much damage to the chosen player.
{T}: Stuffy Doll deals 1 damage to itself.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Spiteful Shadows

Enchant creature
Whenever enchanted creature is dealt damage, it deals that much damage to its controller.

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Mogg Maniac

Whenever Mogg Maniac is dealt damage, it deals that much damage to target opponent or planeswalker.

Star of Extinction

Destroy target land. Star of Extinction deals 20 damage to each creature and each planeswalker.

Coalhauler Swine

Whenever Coalhauler Swine is dealt damage, it deals that much damage to each player.

Stormwild Capridor

Flying
If noncombat damage would be dealt to Stormwild Capridor, prevent that damage. Put a +1/+1 counter on Stormwild Capridor for each 1 damage prevented this way.