Aggressive Urge

Target creature gets +1/+1 until end of turn.
Draw a card.

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.)

Might of the Old Ways

Target creature gets +2/+2 until end of turn.
Coven — Then if you control three or more creatures with different powers, draw a card.

Seedborn Muse

Untap all permanents you control during each other player's untap step.

Stun

Target creature can't block this turn.
Draw a card.

Refresh

Sudden Strength

Target creature gets +3/+3 until end of turn.
Draw a card.

Electrostatic Infantry

Trample
Whenever you cast an instant or sorcery spell, put a +1/+1 counter on Electrostatic Infantry.

Aleatory

Cast this spell only during combat after blockers are declared.
Flip a coin. If you win the flip, target creature gets +1/+1 until end of turn.
Draw a card at the beginning of the next turn's upkeep.

Expedite

Target creature gains haste until end of turn.
Draw a card.

Chaotic Strike

Cast this spell only during combat after blockers are declared.
Flip a coin. If you win the flip, target creature gets +1/+1 until end of turn.
Draw a card.

Neonate's Rush

This spell costs {1} less to cast if you control a Vampire.
Neonate's Rush deals 1 damage to target creature and 1 damage to its controller. Draw a card.

Poison the Blade

Target creature gains deathtouch until end of turn.
Draw a card.

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Arcane Signet

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

Great Train Heist

Spree (Choose one or more additional costs.)
+ {2}{R} — Untap all creatures you control. If it's your combat phase, there is an additional combat phase after this phase.
+ {2} — Creatures you control get +1/+0 and gain first strike until end of turn.
+ {R} — Choose target opponent. Whenever a creature you control deals combat damage to that player this turn, create a tapped Treasure token.

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Leyline of Resonance

If Leyline of Resonance is in your opening hand, you may begin the game with it on the battlefield.
Whenever you cast an instant or sorcery spell that targets only a single creature you control, copy that spell. You may choose new targets for the copy.

Berserk

Cast this spell only before the combat damage step.
Target creature gains trample and gets +X/+0 until end of turn, where X is its power. At the beginning of the next end step, destroy that creature if it attacked this turn.

Crimson Wisps

Target creature becomes red and gains haste until end of turn.
Draw a card.

Storm-Kiln Artist

Storm-Kiln Artist gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.

Command Tower

Coruscation Mage

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Prizefight

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Rampage of the Clans

Destroy all artifacts and enchantments. For each permanent destroyed this way, its controller creates a 3/3 green Centaur creature token.

Unleash Fury

Double the power of target creature until end of turn.

Provoke

Untap target creature you don't control. That creature blocks this turn if able.
Draw a card.

Cultivate

Sol Ring

Sweeping Cleave

Target creature you control gains double strike until end of turn. (Then exile this card. You may cast the artifact later from exile.)

Two-Handed Axe

Whenever equipped creature attacks, double its power until end of turn.
Equip {1}{R}

Two-Handed Axe // Sweeping Cleave

Choose Your Weapon

Choose one —
• Two-Weapon Fighting — Double target creature's power and toughness until end of turn.
• Archery — This spell deals 5 damage to target creature with flying.

Firebrand Archer

Whenever you cast a noncreature spell, Firebrand Archer deals 1 damage to each opponent.

Withstand Death

Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it's still put into its owner's graveyard.)

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.

Feral Instinct

Target creature gets +1/+1 until end of turn.
Draw a card at the beginning of the next turn's upkeep.

Fire Prophecy

Fire Prophecy deals 3 damage to target creature. You may put a card from your hand on the bottom of your library. If you do, draw a card.

Critical Hit

Target creature gains double strike until end of turn.
When you roll a natural 20, return Critical Hit from your graveyard to your hand. (A natural 20 is a roll that displays 20 on the die.)

Crack Open

Destroy target artifact or enchantment. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Charge Through

Target creature gains trample until end of turn.
Draw a card.

Raking Claws

Target creature gains double strike until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Lace with Moonglove

Target creature gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy that creature.)
Draw a card.

Electrostatic Field

Defender
Whenever you cast an instant or sorcery spell, Electrostatic Field deals 1 damage to each opponent.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Psychotic Fury

Target multicolored creature gains double strike until end of turn.
Draw a card.

Zada, Hedron Grinder

Whenever you cast an instant or sorcery spell that targets only Zada, Hedron Grinder, copy that spell for each other creature you control that the spell could target. Each copy targets a different one of those creatures.

Arasta of the Endless Web

Reach
Whenever an opponent casts an instant or sorcery spell, create a 1/2 green Spider creature token with reach.

Sudden Breakthrough

Target creature gets +2/+0 and gains first strike until end of turn.
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Return of the Wildspeaker

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Erebor Flamesmith

Whenever you cast an instant or sorcery spell, Erebor Flamesmith deals 1 damage to each opponent.

Panic

Cast this spell only during combat before blockers are declared.
Target creature can't block this turn.
Draw a card at the beginning of the next turn's upkeep.

Accelerate

Mountain

Brute Force

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

Forest

Antagonize

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

Colossal Might

Target creature gets +4/+2 and gains trample until end of turn.

Guttersnipe

Whenever you cast an instant or sorcery spell, Guttersnipe deals 2 damage to each opponent.

Bothersome Quasit

Menace
Goaded creatures your opponents control can't block.
Whenever you cast a noncreature spell, goad target creature an opponent controls. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

Wilderness Reclamation

At the beginning of your end step, untap all lands you control.

Flick a Coin

Flick a Coin deals 1 damage to any target. You create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Draw a card.

Master Chef

Commander creatures you own have "This creature enters with an additional +1/+1 counter on it" and "Other creatures you control enter with an additional +1/+1 counter on them."

Fists of Flame

Draw a card. Until end of turn, target creature gains trample and gets +1/+0 for each card you've drawn this turn.

Fiery Inscription

When Fiery Inscription enters, the Ring tempts you.
Whenever you cast an instant or sorcery spell, Fiery Inscription deals 2 damage to each opponent.

Assault Strobe

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

Twinferno

Choose one —
• When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.
• Target creature you control gains double strike until end of turn.

Pirate's Pillage

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 artifact: Add one mana of any color.")

Verdant Rebirth

Until end of turn, target creature gains "When this creature dies, return it to its owner's hand."
Draw a card.

Might of the Meek

Target creature gains trample until end of turn. It also gets +1/+0 until end of turn if you control a Mouse.
Draw a card.

Mizzix's Mastery

Exile target card that's an instant or sorcery from your graveyard. For each card exiled this way, copy it, and you may cast the copy without paying its mana cost. Exile Mizzix's Mastery.
Overload {5}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Krenko, Tin Street Kingpin

Whenever Krenko, Tin Street Kingpin attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.

Gold Rush

Create a Treasure token. Until end of turn, up to one target creature gets +2/+2 for each Treasure you control.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.