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.)

Ancient Brass Dragon

Flying
Whenever Ancient Brass Dragon deals combat damage to a player, roll a d20. When you do, put any number of target creature cards with total mana value X or less from graveyards onto the battlefield under your control, where X is the result.

Blood Pact

Target player draws two cards and loses 2 life.

Debt to the Kami

Choose one —
• Target opponent exiles a creature they control.
• Target opponent exiles an enchantment they control.

Mountain

Pointed Discussion

You draw two cards, lose 2 life, then create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Tainted Peak

{T}: Add {C}.
{T}: Add {B} or {R}. Activate only if you control a Swamp.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Goldspan Dragon

Flying, haste
Whenever Goldspan Dragon attacks or becomes the target of a spell, create a Treasure token.
Treasures you control have "{T}, Sacrifice this artifact: Add two mana of any one color."

Coalition Relic

{T}: Add one mana of any color.
{T}: Put a charge counter on Coalition Relic.
At the beginning of your precombat main phase, remove all charge counters from Coalition Relic. Add one mana of any color for each charge counter removed this way.

Dragon Mage

Flying
Whenever Dragon Mage deals combat damage to a player, each player discards their hand, then draws seven cards.

Carnelian Orb of Dragonkind

{T}: Add {R}. If that mana is spent on a Dragon creature spell, it gains haste until end of turn.

Patron of the Arts

When Patron of the Arts enters the battlefield or dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Thrumming Stone

Spells you cast have ripple 4. (Whenever you cast a spell, you may reveal the top four cards of your library. You may cast spells with the same name as that spell from among the revealed cards without paying their mana costs. Put the rest on the bottom of your library.)

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Luxury Suite

Luxury Suite enters the battlefield tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Succumb to Temptation

Graven Cairns

{T}: Add {C}.
{B/R}, {T}: Add {B}{B}, {B}{R}, or {R}{R}.

Swamp

Introduction to Prophecy

Dragonskull Summit

Dragonskull Summit enters the battlefield tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of your postcombat main phase, add {R} for each 1 life your opponents have lost this turn.

Crux of Fate

Choose one —
• Destroy all Dragon creatures.
• Destroy all non-Dragon creatures.

Dragon's Hoard

Whenever a Dragon enters the battlefield under your control, put a gold counter on Dragon's Hoard.
{T}, Remove a gold counter from Dragon's Hoard: Draw a card.
{T}: Add one mana of any color.

Obosh, the Preypiercer

Companion — Your starting deck contains only cards with odd mana values and land cards. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
If a source you control with an odd mana value would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Locket of Yesterdays

Spells you cast cost {1} less to cast for each card with the same name as that spell in your graveyard.

Haunted Ridge

Haunted Ridge enters the battlefield tapped unless you control two or more other lands.
{T}: Add {B} or {R}.

Backdraft Hellkite

Flying
Whenever Backdraft Hellkite attacks, each instant and sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost.

Flay Essence

Exile target creature or planeswalker. You gain life equal to the number of counters on it.

Dragon's Approach

Dragon's Approach deals 3 damage to each opponent. You may exile Dragon's Approach and four cards named Dragon's Approach from your graveyard. If you do, search your library for a Dragon creature card, put it onto the battlefield, then shuffle.
A deck can have any number of cards named Dragon's Approach.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Sol Ring

Reliquary Tower

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

Tor Wauki the Younger

Reach, lifelink
If another source you control would deal noncombat damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
Whenever you cast an instant or sorcery spell, Tor Wauki the Younger deals 2 damage to any target.

Hero's Downfall

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Foreboding Fruit

Target player draws two cards and loses 2 life.
Adamant — If at least three black mana was spent to cast this spell, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Command Tower

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

Blood Money

Destroy all creatures. For each nontoken creature destroyed this way, you create a tapped Treasure token.

Wheel of Misfortune

Each player secretly chooses a number 0 or greater, then all players reveal those numbers simultaneously and determine the highest and lowest numbers revealed this way. Wheel of Misfortune deals damage equal to the highest number to each player who chose that number. Each player who didn't choose the lowest number discards their hand, then draws seven cards.

Bladewing the Risen

Flying
When Bladewing the Risen enters the battlefield, you may return target Dragon permanent card from your graveyard to the battlefield.
{B}{R}: Dragon creatures get +1/+1 until end of turn.

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Knollspine Dragon

Flying
When Knollspine Dragon enters the battlefield, you may discard your hand and draw cards equal to the damage dealt to target opponent this turn.