Inti, Seneschal of the Sun

Whenever you attack, you may discard a card. When you do, put a +1/+1 counter on target attacking creature. It gains trample until end of turn.
Whenever you discard one or more cards, exile the top card of your library. You may play that card until your next end step.

Plains

Organic Extinction

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Destroy all nonartifact creatures.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Ignite the Future

Exile the top three cards of your library. Until the end of your next turn, you may play those cards. If this spell was cast from a graveyard, you may play cards this way without paying their mana costs.
Flashback {7}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Reprieve

Return target spell to its owner's hand.
Draw a card.

Thought Vessel

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

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

Chandra, Torch of Defiance

+1: Exile the top card of your library. You may cast that card. If you don't, Chandra, Torch of Defiance deals 2 damage to each opponent.
+1: Add {R}{R}.
−3: Chandra, Torch of Defiance deals 4 damage to target creature.
−7: You get an emblem with "Whenever you cast a spell, this emblem deals 5 damage to any target."

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Embereth Blaze

Embereth Blaze deals 2 damage to any target. (Then exile this card. You may cast the enchantment later from exile.)

Virtue of Courage

Whenever a source you control deals noncombat damage to an opponent, you may exile that many cards from the top of your library. You may play those cards this turn.

Virtue of Courage // Embereth Blaze

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.

Sundown Pass

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Outpost Siege

As Outpost Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card.
• Dragons — Whenever a creature you control leaves the battlefield, Outpost Siege deals 1 damage to any target.

Commune with Lava

Exile the top X cards of your library. Until the end of your next turn, you may play those cards.

Atsushi, the Blazing Sky

Flying, trample
When Atsushi, the Blazing Sky dies, choose one —
• Exile the top two cards of your library. Until the end of your next turn, you may play those cards.
• Create three Treasure tokens.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Wrenn's Resolve

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Inspired Tinkering

Exile the top three cards of your library. Until the end of your next turn, you may play those cards.
Create three Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mountain

Starnheim Unleashed

Create a 4/4 white Angel Warrior creature token with flying and vigilance. If this spell was foretold, create X of those tokens instead.
Foretell {X}{X}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Commander Liara Portyr

Whenever you attack, spells you cast from exile this turn cost {X} less to cast, where X is the number of players being attacked. Exile the top X cards of your library. Until end of turn, you may cast spells from among those exiled cards.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

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.

Aven Interrupter

Flash
Flying
When Aven Interrupter enters, exile target spell. It becomes plotted. (Its owner may cast it as a sorcery on a later turn without paying its mana cost.)
Spells your opponents cast from graveyards or from exile cost {2} more to cast.

Arcane Signet

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

Terramorphic Expanse

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

Sol Ring

Blood Moon

Anzrag's Rampage

Destroy all artifacts you don't control, then exile the top X cards of your library, where X is the number of artifacts that were put into graveyards from the battlefield this turn. You may put a creature card exiled this way onto the battlefield. It gains haste. Return it to your hand at the beginning of the next end step.

Tavern Brawler

Commander creatures you own have "At the beginning of your upkeep, exile the top card of your library. This creature gets +X/+0 until end of turn, where X is that card's mana value. You may play that card this turn."

Dark-Dweller Oracle

{1}, Sacrifice a creature: Exile the top card of your library. You may play that card this turn. (You still pay its costs. You can play a land this way only if you have an available land play remaining.)

Irascible Wolverine

When Irascible Wolverine enters, exile the top card of your library. Until end of turn, you may play that card.
Plot {2}{R} (You may pay {2}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Tear

Destroy target enchantment.
Fuse (You may cast one or both halves of this card from your hand.)

Wear

Destroy target artifact.
Fuse (You may cast one or both halves of this card from your hand.)

Wear // Tear

Mishra's Research Desk

{1}, {T}, Sacrifice Mishra's Research Desk: Exile the top two cards of your library. Choose one of them. Until the end of your next turn, you may play that card.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Stingerback Terror

Flying, trample
Stingerback Terror gets -1/-1 for each card in your hand.
Plot {2}{R} (You may pay {2}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Showdown of the Skalds

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Exile the top four cards of your library. Until the end of your next turn, you may play those cards.
II, III — Whenever you cast a spell this turn, put a +1/+1 counter on target creature you control.

Glorious Protector

Flash
Flying
When Glorious Protector enters, you may exile any number of non-Angel creatures you control until Glorious Protector leaves the battlefield.
Foretell {2}{W}

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Boros Signet

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Throes of Chaos

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Evolving Wilds

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

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Expel the Interlopers

Choose a number between 0 and 10. Destroy all creatures with power greater than or equal to the chosen number.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Lightning Helix

Lightning Helix deals 3 damage to any target and you gain 3 life.

Clifftop Retreat

Clifftop Retreat enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

Command Tower

Nahiri's Warcrafting

Nahiri's Warcrafting deals 5 damage to target creature, planeswalker, or battle. Look at the top X cards of your library, where X is the excess damage dealt this way. You may exile one of those cards. Put the rest on the bottom of your library in a random order. You may play the exiled card this turn.

March of Reckless Joy

As an additional cost to cast this spell, you may exile any number of red cards from your hand. This spell costs {2} less to cast for each card exiled this way.
Exile the top X cards of your library. You may play up to two of those cards until the end of your next turn.

Pia Nalaar, Consul of Revival

Thopters you control have haste.
Whenever you play a land from exile or cast a spell from exile, create a 1/1 colorless Thopter artifact creature token with flying.

Neyali, Suns' Vanguard

Attacking tokens you control have double strike.
Whenever one or more tokens you control attack a player, exile the top card of your library. During any turn you attacked with a token, you may play that card.

Reckless Impulse

Laelia, the Blade Reforged

Haste
Whenever Laelia, the Blade Reforged attacks, exile the top card of your library. You may play that card this turn.
Whenever one or more cards are put into exile from your library and/or your graveyard, put a +1/+1 counter on Laelia.

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.

Urabrask, Heretic Praetor

Haste
At the beginning of your upkeep, exile the top card of your library. You may play it this turn.
At the beginning of each opponent's upkeep, the next time they would draw a card this turn, instead they exile the top card of their library. They may play it this turn.