Blisterspit Gremlin

{1}, {T}: This creature deals 1 damage to each opponent.
Whenever you cast a noncreature spell, untap this creature.

Livaan, Cultist of Tiamat

Whenever you cast a noncreature spell, target creature gets +X/+0 until end of turn, where X is that spell's mana value.
Choose a Background (You can have a Background as a second commander.)

Psychic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you scry 2.

Mist-Cloaked Herald

Batterhorn

When this creature enters, you may destroy target artifact.

Bloodwater Entity

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, you may put target instant or sorcery card from your graveyard on top of your library.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Ravenform

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying.
Foretell {U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Dispelling Exhale

As an additional cost to cast this spell, you may behold a Dragon. (You may choose a Dragon you control or reveal a Dragon card from your hand.)
Counter target spell unless its controller pays {2}. If a Dragon was beheld, counter that spell unless its controller pays {4} instead.

Angry Rabble

Trample
Whenever you cast a spell with mana value 4 or greater, this creature deals 1 damage to each opponent.
{5}{R}: Put two +1/+1 counters on this creature. Activate only as a sorcery.

Seize the Spoils

As an additional cost to cast this spell, discard a card.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Focus the Mind

This spell costs {2} less to cast if you've cast another spell this turn.
Draw three cards, then discard a card.

Skimming Strike

Tap up to one target creature. Draw a card. (Then shuffle this card into its owner's library.)

Dirgur Island Dragon

Flying
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Dirgur Island Dragon // Skimming Strike

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Conduct Electricity

Conduct Electricity deals 6 damage to target creature and 2 damage to up to one target creature token.

Roughshod Duo

Trample
Whenever you expend 4, target creature you control gets +1/+1 and gains trample until end of turn. (You expend 4 as you spend your fourth total mana to cast spells during a turn.)

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Arcbound Slasher

Modular 4 (This creature enters with four +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Riot (This creature enters with your choice of an additional +1/+1 counter or haste.)

Grapeshot

Grapeshot deals 1 damage to any target.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Beat a Path

Up to two target creatures can't block this turn. (Then exile this card. You may cast the creature later from exile.)

Bellowing Bruiser

Bellowing Bruiser // Beat a Path

Izzet Signet

Frilled Sparkshooter

Menace, reach
This creature enters with a +1/+1 counter on it if an opponent lost life this turn.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Behold the Multiverse

Scry 2, then draw two cards.
Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Arrow Storm

Arrow Storm deals 4 damage to any target.
Raid — If you attacked this turn, instead Arrow Storm deals 5 damage to that permanent or player and the damage can't be prevented.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Kindlespark Duo

{T}: This creature deals 1 damage to target opponent.
Whenever you cast a noncreature spell, untap this creature.

Fiery Intervention

Choose one —
• Fiery Intervention deals 5 damage to target creature.
• Destroy target artifact.

Enter the Enigma

Target creature can't be blocked this turn.
Draw a card.

Negate

Flush Out

Discard a card. If you do, draw two cards. (Then shuffle this card into its owner's library.)

Stormshriek Feral

Flying, haste
{1}{R}: This creature gets +1/+0 until end of turn.

Stormshriek Feral // Flush Out

Capsizing Wave

Return target creature to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Sword Coast Serpent

This creature can't be blocked as long as you've cast a noncreature spell this turn.

Sword Coast Serpent // Capsizing Wave

Bedhead Beastie

Menace (This creature can't be blocked except by two or more creatures.)
Mountaincycling {2} ({2}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Arcbound Tracker

Menace
Modular 2 (This creature enters with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Whenever you cast a spell other than your first spell each turn, put a +1/+1 counter on this creature.

Empty the Warrens

Create two 1/1 red Goblin creature tokens.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Meeting of Minds

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Draw two cards.

Feywild Visitor

Commander creatures you own have "Whenever one or more nontoken creatures you control deal combat damage to a player, you create a 1/1 blue Faerie Dragon creature token with flying."

Dazzling Denial

Counter target spell unless its controller pays {2}. If you control a Bird, counter that spell unless its controller pays {4} instead.

Lórien Revealed

Draw three cards.
Islandcycling {1} ({1}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Sand Augury

Scry 1, then draw a card. (Then exile this card. You may cast the creature later from exile.)

Young Blue Dragon

Young Blue Dragon // Sand Augury

Cinder Storm

Cinder Storm deals 7 damage to any target.

Shiny Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Lightshell Duo

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Lonely Sandbar

This land enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Alania's Pathmaker

When this creature enters, exile the top card of your library. Until the end of your next turn, you may play that card.

Gravitic Punch

Target creature you control deals damage equal to its power to target player.
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.)

Island

Mountain

Pearl of Wisdom

This spell costs {1} less to cast if you control an Otter.
Draw two cards.

Tempest Angler

Whenever you cast a noncreature spell, put a +1/+1 counter on this creature.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Ardent Elementalist

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Kessig Flamebreather

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Forgotten Cave

This land enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Boulderborn Dragon

Flying, vigilance
Whenever this creature attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Goblin Electromancer

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

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Slither Blade

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Cosmotronic Wave

Cosmotronic Wave deals 1 damage to each creature your opponents control. Creatures your opponents control can't block this turn.

Fanged Flames

Devoid (This card has no color.)
Fanged Flames deals 4 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.