Invoke the Firemind

Choose one —
• Draw X cards.
• Invoke the Firemind deals X damage to any target.

Censor

Counter target spell unless its controller pays {1}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Ghitu Lavarunner

As long as there are two or more instant and/or sorcery cards in your graveyard, Ghitu Lavarunner gets +1/+0 and has haste.

Hypersonic Dragon

Flying, haste
You may cast sorcery spells as though they had flash. (You may cast them any time you could cast an instant.)

Adeliz, the Cinder Wind

Flying, haste
Whenever you cast an instant or sorcery spell, Wizards you control get +1/+1 until end of turn.

Shattering Spree

Replicate {R} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Destroy target artifact.

Electrolyze

Electrolyze deals 2 damage divided as you choose among one or two targets.
Draw a card.

Umara Skyfalls

Umara Skyfalls enters tapped.
{T}: Add {U}.

Umara Wizard

Whenever you cast an instant, sorcery, or Wizard spell, Umara Wizard gains flying until end of turn.

Umara Wizard // Umara Skyfalls

Goblin Rally

Create four 1/1 red Goblin creature tokens.

Djinn Illuminatus

({U/R} can be paid with either {U} or {R}.)
Flying
Each instant and sorcery spell you cast has replicate. The replicate cost is equal to its mana cost. (When you cast it, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)

Island

Shock

Pyromatics

Replicate {1}{R} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Pyromatics deals 1 damage to any target.

Izzet Guildgate

Izzet Guildgate enters tapped.
{T}: Add {U} or {R}.

Stormchaser Mage

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

Wizard's Lightning

This spell costs {2} less to cast if you control a Wizard.
Wizard's Lightning deals 3 damage to any target.

Sprite Dragon

Flying, haste
Whenever you cast a noncreature spell, put a +1/+1 counter on Sprite Dragon.

Thunderheads

Replicate {2}{U} (When you cast this spell, copy it for each time you paid its replicate cost.)
Create a 3/3 blue Weird creature token with defender and flying. Exile it at the beginning of the next end step.

Negate

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Izzet Boilerworks

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

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.")

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Direct Current

Direct Current deals 2 damage to any target.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Spikefield Cave

Spikefield Cave enters tapped.
{T}: Add {R}.

Spikefield Hazard

Spikefield Hazard deals 1 damage to any target. If a permanent dealt damage this way would die this turn, exile it instead.

Spikefield Hazard // Spikefield Cave

Wee Dragonauts

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

Cerebral Vortex

Target player draws two cards, then Cerebral Vortex deals damage to that player equal to the number of cards they've drawn this turn.

Erratic Cyclops

Trample
Whenever you cast an instant or sorcery spell, Erratic Cyclops gets +X/+0 until end of turn, where X is that spell's mana value.

Wizard's Retort

This spell costs {1} less to cast if you control a Wizard.
Counter target spell.

Mountain

Crackling Drake

Flying
Crackling Drake's power is equal to the total number of instant and sorcery cards you own in exile and in your graveyard.
When Crackling Drake enters, draw a card.

Counterspell

Glasspool Shore

Glasspool Shore enters tapped.
{T}: Add {U}.

Glasspool Mimic

You may have Glasspool Mimic enter as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.