Mountain

Gut Shot

({R/P} can be paid with either {R} or 2 life.)
Gut Shot deals 1 damage to any target.

Haste
Whenever a creature you control attacks, Hellrider deals 1 damage to the player or planeswalker it's attacking.

Create two 1/1 red Goblin creature tokens.

{T}: Goblin Fireslinger deals 1 damage to target player or planeswalker.

Haste (This creature can attack and {T} as soon as it comes under your control.)
Other Goblin creatures you control get +1/+1 and have haste.

As an additional cost to cast this spell, sacrifice a Goblin.
Goblin Grenade deals 5 damage to any target.

As an additional cost to cast this spell, sacrifice a creature.
Add {R}{R}{R}.

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

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)