Reckless Ransacking

Target creature gets +3/+2 until end of turn. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Antagonize

Target creature gets +4/+3 until end of turn.

Dispel

Kiln Fiend

Whenever you cast an instant or sorcery spell, this creature gets +3/+0 until end of turn.

Lightning Strike

Lightning Strike deals 3 damage to any target.

Mountain

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Assault Strobe

Target creature gains double strike until end of turn. (It deals both first-strike and regular combat damage.)

Nivix Cyclops

Defender
Whenever you cast an instant or sorcery spell, this creature gets +3/+0 until end of turn and can attack this turn as though it didn't have defender.

Brute Strength

Target creature gets +3/+1 and gains trample until end of turn. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Counterspell

Festival Crasher

Whenever you cast an instant or sorcery spell, this creature gets +2/+0 until end of turn.