Rubblebelt Maaka

Bloodrush — {R}, Discard Rubblebelt Maaka: Target attacking creature gets +3/+3 until end of turn.

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Tarfire

Rakdos Cackler

Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

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.)

Burst Lightning

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Burst Lightning deals 2 damage to any target. If this spell was kicked, it deals 4 damage instead.

Mountain

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu the Punisher deals 2 damage to that land's controller.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Hellspark Elemental

Trample, haste
At the beginning of the end step, sacrifice Hellspark Elemental.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Vexing Devil

When Vexing Devil enters, any opponent may have it deal 4 damage to them. If a player does, sacrifice Vexing Devil.

Shard Volley

As an additional cost to cast this spell, sacrifice a land.
Shard Volley deals 3 damage to any target.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Monastery Swiftspear

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)