Bolt Hound

Haste (This creature can attack and {T} as soon as it comes under your control.)
Whenever Bolt Hound attacks, other creatures you control get +1/+0 until end of turn.

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.

Mountain

Soul Sear

Soul Sear deals 5 damage to target creature or planeswalker. That permanent loses indestructible until end of turn.

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.

Shock

Goblin Arsonist

When Goblin Arsonist dies, you may have it deal 1 damage to any target.

Goblin Wizardry

Create two 1/1 red Goblin Wizard creature tokens with prowess. (Whenever you cast a noncreature spell, they get +1/+1 until end of turn.)

Scorching Dragonfire

Scorching Dragonfire deals 3 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Traitorous Greed

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. Add two mana of any one color. (The creature can attack and {T} this turn.)

Hobblefiend

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
{1}, Sacrifice another creature: Put a +1/+1 counter on Hobblefiend.