Katara, Seeking Revenge

As an additional cost to cast this spell, you may waterbend {2}. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)
When Katara enters, draw a card, then discard a card unless her additional cost was paid.
Katara gets +1/+1 for each Lesson card in your graveyard.

Rowdy Snowballers

When this creature enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Zuko, Avatar Hunter

Reach (This creature can block creatures with flying.)
Whenever you cast a red spell, create a 2/2 red Soldier creature token.

Sokka, Bold Boomeranger

When Sokka enters, discard up to two cards, then draw that many cards.
Whenever you cast an artifact or Lesson spell, put a +1/+1 counter on Sokka.

Master Pakku

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Master Pakku becomes tapped, target player mills X cards, where X is the number of Lesson cards in your graveyard. (They put the top X cards of their library into their graveyard.)

Arcane Signet

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

Teo, Spirited Glider

Flying
Whenever one or more creatures you control with flying attack, draw a card, then discard a card. When you discard a nonland card this way, put a +1/+1 counter on target creature you control.

Black Sun's Zenith

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

Desperate Plea

As an additional cost to cast this spell, sacrifice a creature.
Choose one or both —
• Return target creature card from your graveyard to the battlefield if its power is less than or equal to the sacrificed creature's power.
• Destroy target creature.

Treetop Freedom Fighters

Haste
When this creature enters, create a 1/1 white Ally creature token.

Loyal Fire Sage

Firebending 1 (Whenever this creature attacks, add {R}. This mana lasts until end of combat.)
{5}: Create a 1/1 white Ally creature token.

Moku, Meandering Drummer

Whenever you cast a noncreature spell, you may pay {1}. If you do, Moku gets +2/+1 and creatures you control gain haste until end of turn.

Zuko's Offense

Zuko's Offense deals 2 damage to any target.

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.

Professor Zei, Anthropologist

{T}, Discard a card: Draw a card.
{1}, {T}, Sacrifice Professor Zei: Return target instant or sorcery card from your graveyard to your hand. Activate only during your turn.

Zuko's Exile

Exile target artifact, creature, or enchantment. Its controller creates a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Mai, Scornful Striker

First strike
Whenever a player casts a noncreature spell, they lose 2 life.

Fire Nation Turret

At the beginning of combat on your turn, up to one target creature gets +2/+0 and gains firebending 2 until end of turn.
{R}: Put a charge counter on this artifact.
Remove fifty charge counters from this artifact: It deals 50 damage to any target.

Clone Legion

For each creature target player controls, create a token that's a copy of that creature.

Foggy Swamp Spirit Keeper

Lifelink
Whenever you draw your second card each turn, create a 1/1 colorless Spirit creature token with "This token can't block or be blocked by non-Spirit creatures."

First-Time Flyer

Flying
This creature gets +1/+1 as long as there's a Lesson card in your graveyard.

Fire Nation Occupation

When this enchantment enters, create a 2/2 red Soldier creature token with firebending 1. (Whenever it attacks, add {R}. This mana lasts until end of combat.)
Whenever you cast a spell during an opponent's turn, create a 2/2 red Soldier creature token with firebending 1.

Deserter's Disciple

{T}: Another target creature you control with power 2 or less can't be blocked this turn.

Smellerbee, Rebel Fighter

First strike
Other creatures you control have haste.
Whenever Smellerbee attacks, you may discard your hand. If you do, draw cards equal to the number of attacking creatures.

Island

Boiling Rock Rioter

Firebending 1 (Whenever this creature attacks, add {R}. This mana lasts until end of combat.)
Tap an untapped Ally you control: Exile target card from a graveyard.
Whenever this creature attacks, you may cast an Ally spell from among cards you own exiled with this creature.

Princess Yue

When Princess Yue dies, if she was a nonland creature, return this card to the battlefield tapped under your control. She's a land named Moon. She gains "{T}: Add {C}." (She's still legendary.)
{T}: Scry 2.

Jasmine Dragon Tea Shop

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast an Ally spell or activate an ability of an Ally source.
{5}, {T}: Create a 1/1 white Ally creature token.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Mountain

Combustion Technique

Combustion Technique deals damage equal to 2 plus the number of Lesson cards in your graveyard to target creature. If that creature would die this turn, exile it instead.

Katara, Bending Prodigy

At the beginning of your end step, if Katara is tapped, put a +1/+1 counter on her.
Waterbend {6}: Draw a card. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Fire Navy Trebuchet

Defender, reach
Whenever you attack, create a 2/1 colorless Construct artifact creature token with flying named Ballistic Boulder that's tapped and attacking. Sacrifice that token at the beginning of the next end step.

Forecasting Fortune Teller

When this creature enters, create a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Fire Nation Warship

Reach
When this Vehicle dies, create a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)

Azula Always Lies

Choose one or both —
• Target creature gets -1/-1 until end of turn.
• Put a +1/+1 counter on target creature.

The Mechanist, Aerial Artisan

Whenever you cast a noncreature spell, create a Clue token. (It's an artifact with "{2}, Sacrifice this token: Draw a card.")
{T}: Until end of turn, target artifact token you control becomes a 3/1 Construct artifact creature with flying.

Fire Nation's Conquest

Crescent Island Temple

When Crescent Island Temple enters, for each Shrine you control, create a 1/1 red Monk creature token with prowess. (Whenever you cast a noncreature spell, it gets +1/+1 until end of turn.)
Whenever another Shrine you control enters, create a 1/1 red Monk creature token with prowess.

Swamp

Explosive Shot

Explosive Shot deals 4 damage to target creature.

Boiling Rock Prison

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

Zuko, Conflicted

At the beginning of your first main phase, choose one that hasn't been chosen and you lose 2 life —
• Draw a card.
• Put a +1/+1 counter on Zuko.
• Add {R}.
• Exile Zuko, then return him to the battlefield under an opponent's control.

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.)

Bender's Waterskin

Untap this artifact during each other player's untap step.
{T}: Add one mana of any color.

Boomerang Basics

Return target nonland permanent to its owner's hand. If you controlled that permanent, draw a card.

North Pole Patrol

{T}: Untap another target permanent you control.
Waterbend {3}, {T}: Tap target creature an opponent controls. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Longshot, Rebel Bowman

Reach (This creature can block creatures with flying.)
Noncreature spells you cast cost {1} less to cast.
Whenever you cast a noncreature spell, Longshot deals 2 damage to each opponent.

Katara, Waterbending Master

Whenever you cast a spell during an opponent's turn, you get an experience counter.
Whenever Katara attacks, you may draw a card for each experience counter you have. If you do, discard a card.

Flexible Waterbender

Vigilance
Waterbend {3}: This creature has base power and toughness 5/2 until end of turn. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Mai, Jaded Edge

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Exhaust — {3}: Put a double strike counter on Mai. (Activate each exhaust ability only once.)

Fire Nation Palace

This land enters tapped unless you control a basic land.
{T}: Add {R}.
{1}{R}, {T}: Target creature you control gains firebending 4 until end of turn. (Whenever it attacks, add {R}{R}{R}{R}. This mana lasts until end of combat.)

Iroh, Firebending Instructor

Whenever Iroh attacks, attacking creatures get +1/+1 until end of turn.

Zuko, Firebending Master

First strike
Firebending X, where X is the number of experience counters you have. (Whenever this creature attacks, add X {R}. This mana lasts until end of combat.)
Whenever you cast a spell during combat, you get an experience counter.

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.

Mai and Zuko

Firebending 3
You may cast Ally spells and artifact spells as though they had flash.

Gran-Gran

Whenever Gran-Gran becomes tapped, draw a card, then discard a card.
Noncreature spells you cast cost {1} less to cast as long as there are three or more Lesson cards in your graveyard.

Jeong Jeong, the Deserter

Firebending 1 (Whenever this creature attacks, add {R}. This mana lasts until end of combat.)
Exhaust — {3}: Put a +1/+1 counter on Jeong Jeong. When you next cast a Lesson spell this turn, copy it and you may choose new targets for the copy. (Activate each exhaust ability only once.)

Sol Ring

Yue, the Moon Spirit

Flying, vigilance
Waterbend {5}, {T}: You may cast a noncreature spell from your hand without paying its mana cost. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Kyoshi Battle Fan

When this Equipment enters, create a 1/1 white Ally creature token, then attach this Equipment to it.
Equipped creature gets +1/+0.
Equip {2} ({2}:Attach to target creature you control. Equip only as a sorcery.)

Merchant of Many Hats

{2}{B}: Return this card from your graveyard to your hand.

Dramatic Reversal

Untap all nonland permanents you control.

Ty Lee, Chi Blocker

Flash
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Ty Lee enters, tap up to one target creature. It doesn't untap during its controller's untap step for as long as you control Ty Lee.

The Cave of Two Lovers

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create two 1/1 white Ally creature tokens.
II — Search your library for a Mountain or Cave card, reveal it, put it into your hand, then shuffle.
III — Earthbend 3. (Target land you control becomes a 0/0 creature with haste that's still a land. Put three +1/+1 counters on it. When it dies or is exiled, return it to the battlefield tapped.)

Agna Qel'a

This land enters tapped unless you control a basic land.
{T}: Add {U}.
{2}{U}, {T}: Draw a card, then discard a card.

Geyser Leaper

Flying
Waterbend {4}: Draw a card, then discard a card. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Barrels of Blasting Jelly

{1}: Add one mana of any color. Activate only once each turn.
{5}, {T}, Sacrifice this artifact: It deals 5 damage to target creature.

The Blue Spirit

You may cast the first creature spell you cast each turn as though it had flash.
Whenever a nontoken creature you control enters during combat, draw a card.

Ruthless Waterbender

Waterbend {2}: This creature gets +1/+1 until end of turn. Activate only during your turn. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Brainstorm

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

Airship Engine Room

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