Essence Backlash

Counter target creature spell. Essence Backlash deals damage equal to that spell's power to its controller.

Dynacharge

Target creature you control gets +2/+0 until end of turn.
Overload {2}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Goblin Electromancer

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

Nivix Cyclops

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

Island

Izzet Guildgate

This land enters tapped.
{T}: Add {U} or {R}.

Mountain

Izzet Boilerworks

Izzet Boilerworks enters tapped.
When Izzet Boilerworks enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Izzet Chronarch

When Izzet Chronarch enters, return target instant or sorcery card from your graveyard to your hand.

Electrickery

Electrickery deals 1 damage to target creature you don't control.
Overload {1}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Piston-Fist Cyclops

Defender
As long as you've cast an instant or sorcery spell this turn, Piston-Fist Cyclops can attack as though it didn't have defender.

Chemister's Trick

Target creature you don't control gets -2/-0 until end of turn and attacks this turn if able.
Overload {3}{U}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Wee Dragonauts

Flying
Whenever you cast an instant or sorcery spell, Wee Dragonauts gets +2/+0 until end of turn.