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.)

Have

Crimson Wisps

Target creature becomes red and gains haste until end of turn. (It can attack and {T} this turn.)
Draw a card.

Guttersnipe

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

Hero of the Nyxborn

When this creature enters, create a 1/1 white Human Soldier creature token.
Whenever you cast a spell that targets this creature, creatures you control get +1/+0 until end of turn.

Survive the Night

Target creature gets +1/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Phalanx Tactics

Target creature you control gets +2/+1 until end of turn. Each other creature you control gets +1/+1 until end of turn.

Aria of Flame

When this enchantment enters, each opponent gains 10 life.
Whenever you cast an instant or sorcery spell, put a verse counter on this enchantment, then it deals damage equal to the number of verse counters on it to target player or planeswalker.

Akroan Crusader

Heroic — Whenever you cast a spell that targets this creature, create a 1/1 red Soldier creature token with haste. (It can attack and {T} as soon as it comes under your control.)

Leonin Lightscribe

Magecraft — Whenever you cast or copy an instant or sorcery spell, creatures you control get +1/+1 until end of turn.

Manaform Hellkite

Flying
Whenever you cast a noncreature spell, create an X/X red Dragon Illusion creature token with flying and haste, where X is the amount of mana spent to cast that spell. Exile that token at the beginning of the next end step.

Krenko, Tin Street Kingpin

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

Weaver of Lightning

Reach (This creature can block creatures with flying.)
Whenever you cast an instant or sorcery spell, this creature deals 1 damage to target creature an opponent controls.

Skyknight Vanguard

Flying
Whenever this creature attacks, create a 1/1 white Soldier creature token that's tapped and attacking.

Kiln Fiend

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

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. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)

Blessed Breath

Target creature you control gains protection from the color of your choice until end of turn.
Splice onto Arcane {W} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Sejiri Glacier

Sejiri Shelter

Target creature you control gains protection from the color of your choice until end of turn.

Sejiri Shelter // Sejiri Glacier

Storm-Kiln Artist

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

Captain Ripley Vance

Whenever you cast your third spell each turn, put a +1/+1 counter on Captain Ripley Vance, then it deals damage equal to its power to any target.

Defiant Strike

Target creature gets +1/+0 until end of turn.
Draw a card.

Adamant Will

Target creature gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Getting

Anim Pakal, Thousandth Moon

Whenever you attack with one or more non-Gnome creatures, put a +1/+1 counter on Anim Pakal, then create X 1/1 colorless Gnome artifact creature tokens that are tapped and attacking, where X is the number of +1/+1 counters on Anim Pakal.

Light of Hope

Choose one —
• You gain 4 life.
• Destroy target enchantment.
• Put a +1/+1 counter on target creature.

Monastery Swiftspear

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

Young Pyromancer

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

Expedite

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

Slayers' Stronghold

{T}: Add {C}.
{R}{W}, {T}: Target creature gets +2/+0 and gains vigilance and haste until end of turn.

Electrostatic Field

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

Stave Off

Target creature gains protection from the color of your choice until end of turn.

Swift Justice

Until end of turn, target creature gets +1/+0 and gains first strike and lifelink.

Bathe in Light

Radiance — Choose a color. Target creature and each other creature that shares a color with it gain protection from the chosen color until end of turn.

Skyknight Legionnaire

Fight as One

Choose one or both —
• Target Human creature you control gets +1/+1 and gains indestructible until end of turn.
• Target non-Human creature you control gets +1/+1 and gains indestructible until end of turn.

Command Tower

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

Battlefield Promotion

Put a +1/+1 counter on target creature. That creature gains first strike until end of turn. You gain 2 life. (A creature with first strike deals combat damage before creatures without first strike.)

Shelter

Target creature you control gains protection from the color of your choice until end of turn.
Draw a card.

Arena Athlete

Heroic — Whenever you cast a spell that targets this creature, target creature an opponent controls can't block this turn.

Accelerate

Phalanx Leader

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on each creature you control.

Will of the All-Hunter

Target creature gets +2/+2 until end of turn. If it's blocking, instead put two +1/+1 counters on it.
Cycling {2} ({2}, Discard this card: Draw a card.)

Blessed Alliance

Escalate {2} (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Target player gains 4 life.
• Untap up to two target creatures.
• Target opponent sacrifices an attacking creature of their choice.

Raze the Effigy

Choose one —
• Destroy target artifact.
• Target attacking creature gets +2/+2 until end of turn.

Needle Spires

This land enters tapped.
{T}: Add {R} or {W}.
{2}{R}{W}: Until end of turn, this land becomes a 2/1 red and white Elemental creature with double strike. It's still a land.

Nahiri's Stoneblades

Up to two target creatures each get +2/+0 until end of turn.

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 token: Add one mana of any color.")

Seeker of the Way

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

Zada, Hedron Grinder

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

Reckless Charge

Target creature gets +3/+0 and gains haste until end of turn.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Invigorated Rampage

Choose one —
• Target creature gets +4/+0 and gains trample until end of turn.
• Two target creatures each get +2/+0 and gain trample until end of turn.

Gird for Battle

Put a +1/+1 counter on each of up to two target creatures.

Go for Blood

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)
Cycling {1} ({1}, Discard this card: Draw a card.)

Moonrage Brute

First strike
Ward—Pay 3 life.
Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Brutal Cathar

Whenever this creature enters or transforms into Brutal Cathar, exile target creature an opponent controls until this creature leaves the battlefield.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

Brutal Cathar // Moonrage Brute

Boon of Safety

Put a shield counter on target creature. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Scry 1.

Aurelia, Exemplar of Justice

Flying
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
At the beginning of combat on your turn, choose up to one target creature you control. Until end of turn, that creature gets +2/+0, gains trample if it's red, and gains vigilance if it's white.

Loran's Escape

Target artifact or creature gains hexproof and indestructible until end of turn. Scry 1.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. This land deals 1 damage to you.

Clifftop Retreat

This land enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

Arrester's Zeal

Target creature gets +2/+2 until end of turn.
Addendum — If you cast this spell during your main phase, that creature gains flying until end of turn.

Clever Lumimancer

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

Electrostatic Infantry

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

Tenth District Legionnaire

Haste
Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature, then scry 1.

Balefire Liege

Other red creatures you control get +1/+1.
Other white creatures you control get +1/+1.
Whenever you cast a red spell, this creature deals 3 damage to target player or planeswalker.
Whenever you cast a white spell, you gain 3 life.

Spiritualize

Until end of turn, whenever target creature deals damage, you gain that much life.
Draw a card.

Wind-Scarred Crag

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {R} or {W}.

Homestead Courage

Put a +1/+1 counter on target creature you control. It gains vigilance until end of turn.
Flashback {W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Apostle's Blessing

({W/P} can be paid with either {W} or 2 life.)
Target artifact or creature you control gains protection from artifacts or from the color of your choice until end of turn.

Desperate Stand

Strive — This spell costs {R}{W} more to cast for each target beyond the first.
Any number of target creatures each get +2/+0 and gain first strike and vigilance until end of turn.

Light the Way

Choose one —
• Put a +1/+1 counter on target creature or Vehicle. Untap it.
• Return target permanent you control to its owner's hand.

Ashmouth Dragon

Flying
Whenever you cast an instant or sorcery spell, this creature deals 2 damage to any target.

Smoldering Egg

Defender
Whenever you cast an instant or sorcery spell, put a number of ember counters on this creature equal to the amount of mana spent to cast that spell. Then if this creature has seven or more ember counters on it, remove them and transform this creature.

Smoldering Egg // Ashmouth Dragon

Pillarverge Pathway

Needleverge Pathway

Needleverge Pathway // Pillarverge Pathway

Mortal's Ardor

Target creature gets +1/+1 and gains lifelink until end of turn. (Damage dealt by the creature also causes its controller to gain that much life.)

Psychotic Fury

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

Emerge Unscathed

Target creature you control gains protection from the color of your choice until end of turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Vanguard of Brimaz

Vigilance
Heroic — Whenever you cast a spell that targets this creature, create a 1/1 white Cat Soldier creature token with vigilance.

Aisha of Sparks and Smoke

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{R/W}: Aisha of Sparks and Smoke gains first strike until end of turn.
Whenever Aisha deals combat damage, you may cast a sorcery spell from your hand with mana value less than or equal to that damage without paying its mana cost.

Unbounded Potential

Choose one —
• Put a +1/+1 counter on each of up to two target creatures.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Entwine {3}{W} (Choose both if you pay the entwine cost.)

Smelt-Ward Minotaur

Whenever you cast an instant or sorcery spell, target creature an opponent controls can't block this turn.

Guided Strike

Target creature gets +1/+0 and gains first strike until end of turn.
Draw a card.

Rile

Rile deals 1 damage to target creature you control. That creature gains trample until end of turn.
Draw a card.

Furycalm Snarl

As this land enters, you may reveal a Mountain or Plains card from your hand. If you don't, this land enters tapped.
{T}: Add {R} or {W}.

Arcee, Acrobatic Coupe

Living metal (During your turn, this Vehicle is also a creature.)
Whenever you cast a spell that targets one or more creatures or Vehicles you control, put that many +1/+1 counters on Arcee. Convert Arcee.

Arcee, Sharpshooter

More Than Meets the Eye {R}{W} (You may cast this card converted for {R}{W}.)
First strike
{1}, Remove one or more +1/+1 counters from Arcee: It deals that much damage to target creature. Convert Arcee.

Arcee, Sharpshooter // Arcee, Acrobatic Coupe

Mountain

Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Rosnakht, Heir of Rohgahh

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Heroic — Whenever you cast a spell that targets Rosnakht, create a 0/1 red Kobold creature token named Kobolds of Kher Keep.

Castle Embereth

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.

Swiftblade Vindicator

Double strike (This creature deals both first-strike and regular combat damage.)
Vigilance (Attacking doesn't cause this creature to tap.)
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Professional Face-Breaker

Menace
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token.
Sacrifice a Treasure: Exile the top card of your library. You may play that card this turn.

Coordinated Assault

Up to two target creatures each get +1/+0 and gain first strike until end of turn. (They deal combat damage before creatures without first strike.)

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.

Temple of Triumph

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {R} or {W}.

Reckless Rage

Reckless Rage deals 4 damage to target creature you don't control and 2 damage to target creature you control.

Samut's Sprint

Target creature gets +2/+1 and gains haste until end of turn. Scry 1.

Boros Garrison

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {R}{W}.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Assault Strobe

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