Burn at the Stake

As an additional cost to cast this spell, tap any number of untapped creatures you control.
Burn at the Stake deals damage to any target equal to three times the number of creatures tapped this way.

Cavalcade of Calamity

Whenever a creature you control with power 1 or less attacks, Cavalcade of Calamity deals 1 damage to the player or planeswalker that creature is attacking.

Seething Song

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Mana Geyser

Add {R} for each tapped land your opponents control.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Massive Raid

Massive Raid deals damage to any target equal to the number of creatures you control.

Jaya, Venerated Firemage

If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
−2: Jaya, Venerated Firemage deals 2 damage to any target.

Arms Dealer

{1}{R}, Sacrifice a Goblin: Arms Dealer deals 4 damage to target creature.

Last-Ditch Effort

Sacrifice any number of creatures. Last-Ditch Effort deals that much damage to any target.

Goblin War Strike

Goblin War Strike deals damage to target player or planeswalker equal to the number of Goblins you control.

Voracious Dragon

Flying
Devour 1 (As this enters, you may sacrifice any number of creatures. This creature enters with that many +1/+1 counters on it.)
When Voracious Dragon enters, it deals damage to any target equal to twice the number of Goblins it devoured.