Mountain

Arcane Signet

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

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Hallowed Fountain

({T}: Add {W} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Island

Forest

Wooded Foothills

{T}, Pay 1 life, Sacrifice this land: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Ugin, Eye of the Storms

When you cast this spell, exile up to one target permanent that's one or more colors.
Whenever you cast a colorless spell, exile up to one target permanent that's one or more colors.
+2: You gain 3 life and draw a card.
0: Add {C}{C}{C}.
−11: Search your library for any number of colorless nonland cards, exile them, then shuffle. Until end of turn, you may cast those cards without paying their mana costs.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. This artifact deals 1 damage to you.

Chameleon, Master of Disguise

You may have Chameleon enter as a copy of a creature you control, except his name is Chameleon, Master of Disguise.
Mayhem {2}{U} (You may cast this card from your graveyard for {2}{U} if you discarded it this turn. Timing rules still apply.)

Overwhelming Stampede

Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.

Shorikai, Genesis Engine

{1}, {T}: Draw two cards, then discard a card. Create a 1/1 colorless Pilot creature token with "This token crews Vehicles as though its power were 2 greater."
Crew 8 (Tap any number of creatures you control with total power 8 or more: This Vehicle becomes an artifact creature until end of turn.)

Rishkar's Expertise

Draw cards equal to the greatest power among creatures you control.
You may cast a spell with mana value 5 or less from your hand without paying its mana cost.

Reflection of Kiki-Jiki

{1}, {T}: Create a token that's a copy of another target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Fable of the Mirror-Breaker

(As this Saga enters and after your draw step, add a lore counter.)
I — Create a 2/2 red Goblin Shaman creature token with "Whenever this token attacks, create a Treasure token."
II — You may discard up to two cards. If you do, draw that many cards.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Fable of the Mirror-Breaker // Reflection of Kiki-Jiki

Ouroboroid

At the beginning of combat on your turn, put X +1/+1 counters on each creature you control, where X is this creature's power.

Clever Concealment

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Any number of target nonland permanents you control phase out. (Treat them and anything attached to them as though they don't exist until your next turn.)

Soporific Springs

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Sink into Stupor

Return target spell or nonland permanent an opponent controls to its owner's hand.

Sink into Stupor // Soporific Springs

Lunar Insight

Draw a card for each different mana value among nonland permanents you control.

Impostor Syndrome

Whenever a nontoken creature you control deals combat damage to a player, create a token that's a copy of it, except it isn't legendary.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Kutzil, Malamet Exemplar

Your opponents can't cast spells during your turn.
Whenever one or more creatures you control each with power greater than its base power deals combat damage to a player, draw a card.

Aragorn, the Uniter

Whenever you cast a white spell, create a 1/1 white Human Soldier creature token.
Whenever you cast a blue spell, scry 2.
Whenever you cast a red spell, Aragorn deals 3 damage to target opponent.
Whenever you cast a green spell, target creature gets +4/+4 until end of turn.

Maximum Carnage

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Until your next turn, each creature attacks each combat if able and attacks a player other than you if able.
II — Add {R}{R}{R}.
III — This Saga deals 5 damage to each opponent.

Plains

Roxanne, Starfall Savant

Whenever Roxanne enters or attacks, create a tapped colorless artifact token named Meteorite with "When this token enters, it deals 2 damage to any target" and "{T}: Add one mana of any color."
Whenever you tap an artifact token for mana, add one mana of any type that artifact token produced.

Forth Eorlingas!

Create X 2/2 red Human Knight creature tokens with trample and haste.
Whenever one or more creatures you control deal combat damage to one or more players this turn, you become the monarch.

Breeding Pool

({T}: Add {G} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Scalding Tarn

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Commercial District

({T}: Add {R} or {G}.)
This land enters tapped.
When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Boros Signet

Lush Portico

({T}: Add {G} or {W}.)
This land enters tapped.
When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Gogo, Mysterious Mime

At the beginning of combat on your turn, you may have Gogo become a copy of another target creature you control until end of turn, except its name is Gogo, Mysterious Mime. If you do, Gogo and that creature each get +2/+0 and gain haste until end of turn and attack this turn if able.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on this creature.

Vaultborn Tyrant

Trample
Whenever this creature or another creature you control with power 4 or greater enters, you gain 3 life and draw a card.
When this creature dies, if it's not a token, create a token that's a copy of it, except it's an artifact in addition to its other types.

Azorius Signet

Talisman of Conviction

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

High Fae Trickster

Flash (You may cast this spell any time you could cast an instant.)
Flying
You may cast spells as though they had flash.

Double Stroke

Hidden agenda (Start the game with this conspiracy face down in the command zone and secretly choose a card name. You may turn this conspiracy face up any time and reveal that name.)
Whenever you cast an instant or sorcery spell with the chosen name, you may copy it. You may choose new targets for the copy.

Expropriate

Council's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one. For each money vote, choose a permanent owned by the voter and gain control of it. Exile Expropriate.

Mother of Runes

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

Twinflame Tyrant

Flying
If a source you control would deal damage to an opponent or a permanent an opponent controls, it deals double that damage instead.

Starting Town

This land enters tapped unless it's your first, second, or third turn of the game.
{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color.

Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Izzet Signet

Mirri, Weatherlight Duelist

First strike
Whenever Mirri attacks, each opponent can't block with more than one creature this combat.
As long as Mirri is tapped, no more than one creature can attack you each combat.

Triumph of the Hordes

Until end of turn, creatures you control get +1/+1 and gain trample and infect. (Creatures with infect deal damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Return of the Wildspeaker

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Goldspan Dragon

Flying, haste
Whenever this creature 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."