Heartfire Immolator

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{R}, Sacrifice Heartfire Immolator: It deals damage equal to its power to target creature or planeswalker.

Bone Pit Brute

Menace (This creature can't be blocked except by two or more creatures.)
When Bone Pit Brute enters, target creature gets +4/+0 until end of turn.

Bloodrage Brawler

When Bloodrage Brawler enters, discard a card.

Hamletback Goliath

Whenever another creature enters, you may put X +1/+1 counters on Hamletback Goliath, where X is that creature's power.

Mountain

Thriving Bluff

Thriving Bluff enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Onakke Ogre

Unleash Fury

Double the power of target creature until end of turn.

Turret Ogre

Reach (This creature can block creatures with flying.)
When Turret Ogre enters, if you control another creature with power 4 or greater, Turret Ogre deals 2 damage to each opponent.

Borderland Marauder

Whenever Borderland Marauder attacks, it gets +2/+0 until end of turn.

Furious Rise

At the beginning of your end step, if you control a creature with power 4 or greater, exile the top card of your library. You may play that card until you exile another card with Furious Rise.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Sarkhan's Unsealing

Whenever you cast a creature spell with power 4, 5, or 6, Sarkhan's Unsealing deals 4 damage to any target.
Whenever you cast a creature spell with power 7 or greater, Sarkhan's Unsealing deals 4 damage to each opponent and each creature and planeswalker they control.

Inferno Hellion

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
At the beginning of each end step, if Inferno Hellion attacked or blocked this turn, its owner shuffles it into their library.