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.

Zuko, Exiled Prince

Firebending 3 (Whenever this creature attacks, add {R}{R}{R}. This mana lasts until end of combat.)
{3}: Exile the top card of your library. You may play that card this turn.

Swamp

Hellkite Charger

Flying, haste
Whenever this creature attacks, you may pay {5}{R}{R}. If you do, untap all attacking creatures and after this phase, there is an additional combat phase.

Bolt Bend

This spell costs {3} less to cast if you control a creature with power 4 or greater.
Change the target of target spell or ability with a single target.

Mountain

Shock

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Iroh's Demonstration

Choose one —
• Iroh's Demonstration deals 1 damage to each creature your opponents control.
• Iroh's Demonstration deals 4 damage to target creature.

Thriving Heath

This land enters tapped. As it enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.

Gix, Yawgmoth Praetor

Whenever a creature deals combat damage to one of your opponents, its controller may pay 1 life. If they do, they draw a card.
{4}{B}{B}{B}, Discard X cards: Exile the top X cards of target opponent's library. You may play lands and cast spells from among cards exiled this way without paying their mana costs.

Misty Palms Oasis

This land enters tapped.
{T}: Add {W} or {B}.
{4}, {T}, Sacrifice this land: Draw a card.

Zenith Festival

Exile the top X cards of your library. You may play them until the end of your next turn.
Harmonize {X}{R}{R} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by an amount of generic mana equal to its power. Then exile this spell.)

Fiery Confluence

Choose three. You may choose the same mode more than once.
• Fiery Confluence deals 1 damage to each creature.
• Fiery Confluence deals 2 damage to each opponent.
• Destroy target artifact.

The Flux

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after VI.)
I — This Saga deals 4 damage to target creature an opponent controls.
II, III, IV, V — Exile the top card of your library. You may play that card this turn.
VI — Add six {R}.

Leyline Tyrant

Flying
You don't lose unspent red mana as steps and phases end.
When this creature dies, you may pay any amount of {R}. When you do, it deals that much damage to any target.

Savage Beating

Cast this spell only during combat on your turn.
Choose one —
• Creatures you control gain double strike until end of turn.
• Untap all creatures you control. After this phase, there is an additional combat phase.
Entwine {1}{R} (Choose both if you pay the entwine cost.)

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Zuko's Conviction

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Return target creature card from your graveyard to your hand. If this spell was kicked, instead put that card onto the battlefield tapped.

Firebending Lesson

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Firebending Lesson deals 2 damage to target creature. If this spell was kicked, it deals 5 damage to that creature instead.

Plains

Quintorius Kand

Whenever you cast a spell from exile, Quintorius Kand deals 2 damage to each opponent and you gain 2 life.
+1: Create a 3/2 red and white Spirit creature token.
−3: Discover 4.
−6: Exile any number of target cards from your graveyard. Add {R} for each card exiled this way. You may play those cards this turn.

Sokka's Sword Training

Target creature gets +2/+2 until end of turn.
Create a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Fire Lord Zuko

Firebending X, where X is Fire Lord Zuko's power. (Whenever this creature attacks, add X {R}. This mana lasts until end of combat.)
Whenever you cast a spell from exile and whenever a permanent you control enters from exile, put a +1/+1 counter on each creature you control.

Fire Lord Ozai

Whenever Fire Lord Ozai attacks, you may sacrifice another creature. If you do, add an amount of {R} equal to the sacrificed creature's power. Until end of combat, you don't lose this mana as steps end.
{6}: Exile the top card of each opponent's library. Until end of turn, you may play one of those cards without paying its mana cost.

Airbending Lesson

Airbend target nonland permanent. (Exile it. While it's exiled, its owner may cast it for {2} rather than its mana cost.)
Draw a card.

Vedalken Orrery

You may cast spells as though they had flash.

Yasmin Khan

{T}: Exile the top card of your library. Until your next end step, you may play it.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Thriving Moor

This land enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Iroh, Dragon of the West

Haste
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, each creature you control with a counter on it gains firebending 2 until end of turn. (Whenever it attacks, add {R}{R}. This mana lasts until end of combat.)

Thriving Bluff

This land enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Embrace the Unknown

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Sun Warriors

Firebending X, where X is the number of creatures you control. (Whenever this creature attacks, add X {R}. This mana lasts until end of combat.)
{5}: Create a 1/1 white Ally creature token.

Electro, Assaulting Battery

Flying
You don't lose unspent red mana as steps and phases end.
Whenever you cast an instant or sorcery spell, add {R}.
When Electro leaves the battlefield, you may pay {X}. When you do, he deals X damage to target player.

Grim Monolith

This artifact doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap this artifact.

Imperial Seal

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Light Up the Stage

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Solstice Revelations

Exile cards from the top of your library until you exile a nonland card. You may cast that card without paying its mana cost if the spell's mana value is less than the number of Mountains you control. If you don't cast that card this way, put it into your hand.
Flashback {6}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)