Simic Growth Chamber

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

Scoured Barrens

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

Rith's Grove

When this land enters, sacrifice it unless you return a non-Lair land you control to its owner's hand.
{T}: Add {R}, {G}, or {W}.

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker of their choice.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Roost Seek

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. (Also shuffle this card.)

Sagu Wildling

Flying
When this creature enters, you gain 3 life.

Sagu Wildling // Roost Seek

Dragonstorm Forecaster

{2}, {T}: Search your library for a card named Dragonstorm Globe or Boulderborn Dragon, reveal it, put it into your hand, then shuffle.

Raking Claws

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

Terramorphic Expanse

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

Betor, Kin to All

Flying
At the beginning of your end step, if creatures you control have total toughness 10 or greater, draw a card. Then if creatures you control have total toughness 20 or greater, untap each creature you control. Then if creatures you control have total toughness 40 or greater, each opponent loses half their life, rounded up.

Coil and Catch

Draw three cards, then discard a card. (Then shuffle this card into its owner's library.)

Marang River Regent

Flying
When this creature enters, return up to two other target nonland permanents to their owners' hands.

Marang River Regent // Coil and Catch

Mountain

Tranquil Cove

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

Opulent Palace

This land enters tapped.
{T}: Add {B}, {G}, or {U}.

Rampant Growth

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

Jade Orb of Dragonkind

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, it enters with an additional +1/+1 counter on it and gains hexproof until your next turn. (It can't be the target of spells or abilities your opponents control.)

Scorching Dragonfire

Scorching Dragonfire deals 3 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Boulderborn Dragon

Flying, vigilance
Whenever this creature attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Cultivate

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.

Troll of Khazad-dûm

This creature can't be blocked except by three or more creatures.
Swampcycling {1} ({1}, Discard this card: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.)

Mardu Monument

When this artifact enters, search your library for a basic Mountain, Plains, or Swamp card, reveal it, put it into your hand, then shuffle.
{2}{R}{W}{B}, {T}, Sacrifice this artifact: Create three 1/1 red Warrior creature tokens. They gain menace and haste until end of turn. Activate only as a sorcery. (A creature with menace can't be blocked except by two or more creatures.)

So Shiny

Enchant creature
When this Aura enters, if you control a token, tap enchanted creature, then scry 2.
Enchanted creature doesn't untap during its controller's untap step.

Ringing Strike Mastery

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
Enchanted creature has "{5}: Untap this creature."

Clarion Conqueror

Flying
Activated abilities of artifacts, creatures, and planeswalkers can't be activated.

Arcane Flight

Enchant creature
Enchanted creature gets +1/+1 and has flying.

Piercing Exhale

As an additional cost to cast this spell, you may behold a Dragon. (You may choose a Dragon you control or reveal a Dragon card from your hand.)
Target creature you control deals damage equal to its power to target creature or planeswalker. If a Dragon was beheld, surveil 2.

Roamer's Routine

Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Harmonize {4}{G} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile this spell.)

Dispelling Exhale

As an additional cost to cast this spell, you may behold a Dragon. (You may choose a Dragon you control or reveal a Dragon card from your hand.)
Counter target spell unless its controller pays {2}. If a Dragon was beheld, counter that spell unless its controller pays {4} instead.

Petty Revenge

Destroy target creature with power 3 or less. (Then shuffle this card into its owner's library.)

Disruptive Stormbrood

Flying
When this creature enters, destroy up to one target artifact or enchantment.

Disruptive Stormbrood // Petty Revenge

Forfend

Prevent all damage that would be dealt to creatures this turn.

Maelstrom of the Spirit Dragon

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Dragon spell or an Omen spell.
{4}, {T}, Sacrifice this land: Search your library for a Dragon card, reveal it, put it into your hand, then shuffle.

Azorius Chancery

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

Forest

Molten Exhale

You may cast this spell as though it had flash if you behold a Dragon as an additional cost to cast it. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.)
Molten Exhale deals 4 damage to target creature or planeswalker.

Ureni's Rebuff

Return target creature to its owner's hand.
Harmonize {5}{U} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile this spell.)

Signaling Roar

Create a 2/2 white Soldier creature token. (Then shuffle this card into its owner's library.)

Riling Dawnbreaker

Flying, vigilance
At the beginning of combat on your turn, another target creature you control gets +1/+0 until end of turn.

Riling Dawnbreaker // Signaling Roar

Wingspan Stride

Enchant creature
Enchanted creature gets +1/+1 and has flying.
{2}{U}: Return this Aura to its owner's hand.

Encroaching Dragonstorm

When this enchantment enters, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.
When a Dragon you control enters, return this enchantment to its owner's hand.

Ganax, Astral Hunter

Flying
Whenever Ganax or another Dragon you control enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Choose a Background (You can have a Background as a second commander.)

Mystic Monastery

This land enters tapped.
{T}: Add {U}, {R}, or {W}.

Death Begets Life

Destroy all creatures and enchantments. Draw a card for each permanent destroyed this way.

Evolving Wilds

Dismal Backwater

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

Island

Alesha's Legacy

Target creature you control gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Absorb Essence

Target creature gets +2/+2 and gains lifelink and hexproof until end of turn. (Then shuffle this card into its owner's library.)

Purging Stormbrood

Flying
Ward—Pay 2 life.
When this creature enters, remove all counters from up to one target creature.

Purging Stormbrood // Absorb Essence

Strategic Betrayal

Target opponent exiles a creature they control and their graveyard.

Dusk Sight

Put a +1/+1 counter on up to one target creature. Draw a card. (Then shuffle this card into its owner's library.)

Feral Deathgorger

Flying, deathtouch
When this creature enters, exile up to two target cards from a single graveyard.

Feral Deathgorger // Dusk Sight

Sultai Monument

When this artifact enters, search your library for a basic Swamp, Forest, or Island card, reveal it, put it into your hand, then shuffle.
{2}{B}{G}{U}, {T}, Sacrifice this artifact: Create two 2/2 black Zombie Druid creature tokens. Activate only as a sorcery.

Dragonstorm Globe

Each Dragon you control enters with an additional +1/+1 counter on it.
{T}: Add one mana of any color.

The Grey Havens

When The Grey Havens enters, scry 1.
{T}: Add {C}.
{T}: Add one mana of any color among legendary creature cards in your graveyard.

Sinister Monolith

At the beginning of combat on your turn, each opponent loses 1 life and you gain 1 life.
{T}, Pay 2 life, Sacrifice this artifact: Draw two cards. Activate only as a sorcery.

Sonic Shrieker

Flying
When this creature enters, it deals 2 damage to any target and you gain 2 life. If a player is dealt damage this way, they discard a card.

The Ur-Dragon

Eminence — As long as The Ur-Dragon is in the command zone or on the battlefield, other Dragon spells you cast cost {1} less to cast.
Flying
Whenever one or more Dragons you control attack, draw that many cards, then you may put a permanent card from your hand onto the battlefield.

Bloodfell Caves

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

Channeled Dragonfire

Channeled Dragonfire deals 2 damage to any target.
Harmonize {5}{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 {X}, where X is its power. Then exile this spell.)

Plains

Boros Garrison

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

Frontier Bivouac

This land enters tapped.
{T}: Add {G}, {U}, or {R}.

Skimming Strike

Tap up to one target creature. Draw a card. (Then shuffle this card into its owner's library.)

Dirgur Island Dragon

Flying
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Dirgur Island Dragon // Skimming Strike

Zombie Druid

Glacial Dragonhunt

Draw a card, then you may discard a card. When you discard a nonland card this way, Glacial Dragonhunt deals 3 damage to target creature.
Harmonize {4}{U}{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 {X}, where X is its power. Then exile this spell.)

Aggressive Negotiations

Target opponent reveals their hand. You choose a nonland card from it and exile that card. Put a +1/+1 counter on up to one target creature you control.

Soldier

Chilling Screech

Counter target spell with mana value 2 or less. (Then shuffle this card into its owner's library.)

Runescale Stormbrood

Flying
Whenever you cast a noncreature spell or a Dragon spell, this creature gets +2/+0 until end of turn.

Runescale Stormbrood // Chilling Screech

Rapacious Dragon

Flying
When this creature enters, create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Temple of Abandon

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 {G}.

Shrine of the Forsaken Gods

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless spells. Activate only if you control seven or more lands.

The Temporal Anchor

At the beginning of your upkeep, scry 2.
Whenever you choose to put one or more cards on the bottom of your library while scrying, exile that many cards from the bottom of your library.
During your turn, you may play cards exiled with The Temporal Anchor.

Garruk's Uprising

When this enchantment enters, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever a creature you control with power 4 or greater enters, draw a card.

Firespitter Whelp

Flying
Whenever you cast a noncreature or Dragon spell, this creature deals 1 damage to each opponent.

Swiftwater Cliffs

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

Warrior

Whenever this creature and at least one other creature token attack, put a +1/+1 counter on this creature.

Thornwood Falls

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

Swamp

Jungle Hollow

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

Osseous Exhale

As an additional cost to cast this spell, you may behold a Dragon. (You may choose a Dragon you control or reveal a Dragon card from your hand.)
Osseous Exhale deals 5 damage to target attacking or blocking creature. If a Dragon was beheld, you gain 2 life.

Flush Out

Discard a card. If you do, draw two cards. (Then shuffle this card into its owner's library.)

Stormshriek Feral

Flying, haste
{1}{R}: This creature gets +1/+0 until end of turn.

Stormshriek Feral // Flush Out

Dracogenesis

You may cast Dragon spells without paying their mana costs.

Auroral Procession

Return target card from your graveyard to your hand.

Aura Graft

Gain control of target Aura that's attached to a permanent. Attach it to another permanent it can enchant.

Corroding Dragonstorm

When this enchantment enters, each opponent loses 2 life and you gain 2 life. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
When a Dragon you control enters, return this enchantment to its owner's hand.

Temple of Malady

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 {B} or {G}.

Ureni, the Song Unending

Flying, protection from white and from black
When Ureni enters, it deals X damage divided as you choose among any number of target creatures and/or planeswalkers your opponents control, where X is the number of lands you control.

Orzhov Basilica

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

Temur Monument

When this artifact enters, search your library for a basic Forest, Island, or Mountain card, reveal it, put it into your hand, then shuffle.
{3}{G}{U}{R}, {T}, Sacrifice this artifact: Create a 5/5 green Elephant creature token. Activate only as a sorcery.

Dragonlord's Servant

Dragon spells you cast cost {1} less to cast.

Inspiring Roar

Put a +1/+1 counter on each creature you control.

Sol Ring

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Red Dragon

Flying
Fire Breath — When this creature enters, it deals 4 damage to each opponent.

Arcane Signet

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

Embermouth Sentinel

When this creature enters, you may search your library for a basic land card, reveal it, then shuffle and put that card on top. If you control a Dragon, put that card onto the battlefield tapped instead.