Roiling Vortex

At the beginning of each player's upkeep, this enchantment deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, this enchantment deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.

Phyrexian Fleshgorger

Prototype {1}{B}{B} — 3/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Menace, lifelink
Ward—Pay life equal to this creature's power.

Yavimaya, Cradle of Growth

Each land is a Forest in addition to its other land types.

Domri, Anarch of Bolas

Creatures you control get +1/+0.
+1: Add {R} or {G}. Creature spells you cast this turn can't be countered.
−2: Target creature you control fights target creature you don't control.

Blood Moon

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Boltwave

Boltwave deals 3 damage to each opponent.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Tyrant of Discord

When this creature enters, target opponent chooses a permanent they control at random and sacrifices it. If a nonland permanent is sacrificed this way, repeat this process.

Geosurge

Add {R}{R}{R}{R}{R}{R}{R}. Spend this mana only to cast artifact or creature spells.

Rift Bolt

Rift Bolt deals 3 damage to any target.
Suspend 1—{R} (Rather than cast this card from your hand, you may pay {R} and exile it with a time counter on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Skullcrack

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

Screaming Nemesis

Haste
Whenever this creature is dealt damage, it deals that much damage to any other target. If a player is dealt damage this way, they can't gain life for the rest of the game.

Sire of Seven Deaths

First strike, vigilance
Menace, trample
Reach, lifelink
Ward—Pay 7 life.

Eidolon of the Great Revel

Whenever a player casts a spell with mana value 3 or less, this creature deals 2 damage to that player.