Sierra, Nuka's Biggest Fan

The Nuka-Cola Challenge — Whenever one or more creatures you control deal combat damage to a player, put a quest counter on Sierra and create a Food token.
Whenever you sacrifice a Food, target creature you control gets +X/+X until end of turn, where X is the number of quest counters on Sierra.

Mjölnir, Storm Hammer

When Mjölnir enters, attach it to target legendary creature you control.
Whenever equipped creature attacks, tap target creature defending player controls and put a stun counter on it. Then Mjölnir deals damage to each opponent equal to the number of tapped creatures that opponent controls.
Equip {4}

Tax Collector

When this creature enters, choose one —
• Tax — Until your next turn, spells your opponents cast cost {1} more to cast.
• Arrest — Detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Citadel Gate

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

Kassandra, Eagle Bearer

Haste
When Kassandra enters, search your graveyard, hand, and library for a card named The Spear of Leonidas, put it onto the battlefield, then shuffle.
Whenever a creature you control with a legendary Equipment attached to it deals combat damage to a player, draw a card.

Smoke Bomb

Flash
All creatures have shroud. (They can't be the targets of spells or abilities.)
At the beginning of your upkeep, sacrifice this artifact. When you do, target creature you control can't be blocked this turn.

Tori D'Avenant, Fury Rider

Vigilance, trample
Whenever Tori D'Avenant attacks, all other attacking creatures you control get +1/+1 until end of turn. Other red attacking creatures you control gain trample until end of turn. Untap each other white attacking creature you control.

Sanctify

Destroy target artifact or enchantment. You gain 3 life.

Shiny Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Caduceus, Staff of Hermes

Equipped creature has lifelink.
As long as you have 30 or more life, equipped creature gets +5/+5 and has indestructible and "Prevent all damage that would be dealt to this creature."
Equip {W}{W}

Mountain

Suq'Ata Lancer

Haste
Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)

Tiana, Ship's Caretaker

Flying, first strike
Whenever an Aura or Equipment you control is put into a graveyard from the battlefield, you may return that card to its owner's hand at the beginning of the next end step.

The Animus

At the beginning of your end step, exile up to one target legendary creature card from a graveyard with a memory counter on it.
{T}: Until your next turn, target legendary creature you control becomes a copy of target creature card in exile with a memory counter on it. Activate only as a sorcery.

Discerning Financier

At the beginning of your upkeep, if an opponent controls more lands than you, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
{2}{W}: Choose another player. That player gains control of target Treasure you control. You draw a card.

Adamant Will

Target creature gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Orim's Thunder

Kicker {R} (You may pay an additional {R} as you cast this spell.)
Destroy target artifact or enchantment. If this spell was kicked, it deals damage equal to that permanent's mana value to target creature.

Smoldering Crater

This land enters tapped.
{T}: Add {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Javelin of Lightning

Flash
When this Equipment enters, attach it to target creature you control.
During your turn, equipped creature gets +2/+0 and has first strike.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

War Flare

Creatures you control get +2/+1 until end of turn. Untap those creatures.

Ezio, Brash Novice

Whenever Ezio attacks, put a +1/+1 counter on it.
As long as Ezio has two or more counters on it, it has first strike and is an Assassin in addition to its other types.

Volatile Wanderglyph

Whenever this creature becomes tapped, you may discard a card. If you do, draw a card.

Chain Lightning

Chain Lightning deals 3 damage to any target. Then that player or that permanent's controller may pay {R}{R}. If the player does, they may copy this spell and may choose a new target for that copy.

Clifftop Retreat

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

Legion Loyalty

Creatures you control have myriad. (Whenever a creature with myriad attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Valduk, Keeper of the Flame

At the beginning of combat on your turn, for each Aura and Equipment attached to Valduk, create a 3/1 red Elemental creature token with trample and haste. Exile those tokens at the beginning of the next end step.

Martial Impetus

Enchant creature
Enchanted creature gets +1/+1 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, each other creature that's attacking one of your opponents gets +1/+1 until end of turn.

Haystack

{2}, {T}: Target creature you control phases out. (Treat it and anything attached to it as though they don't exist until your next turn.)

Plains

Swords to Plowshares

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

Shadowfax, Lord of Horses

Horses you control have haste. (They can attack and {T} as soon as they come under your control.)
Whenever Shadowfax attacks, you may put a creature card with lesser power from your hand onto the battlefield tapped and attacking.

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Brazen Blademaster

Whenever this creature attacks while you control two or more artifacts, it gets +2/+1 until end of turn.

Raid Bombardment

Whenever a creature you control with power 2 or less attacks, this enchantment deals 1 damage to the player or planeswalker that creature is attacking.

Bayek of Siwa

Double strike
During your turn, other historic creatures you control have double strike.
Disguise {1}{R}{W} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Memorial to Glory

This land enters tapped.
{T}: Add {W}.
{3}{W}, {T}, Sacrifice this land: Create two 1/1 white Soldier creature tokens.

Overpowering Attack

Freerunning {2}{R} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
Untap all creatures you control that attacked this turn. If it's your main phase, there is an additional combat phase after this phase, followed by an additional main phase.

Alexios, Deimos of Kosmos

Trample
Alexios attacks each combat if able, can't be sacrificed, and can't attack its owner.
At the beginning of each player's upkeep, that player gains control of Alexios, untaps it, and puts a +1/+1 counter on it. It gains haste until end of turn.

Reconstruct History

Return up to one target artifact card, up to one target enchantment card, up to one target instant card, up to one target sorcery card, and up to one target planeswalker card from your graveyard to your hand.
Exile Reconstruct History.

Assemble the Legion

At the beginning of your upkeep, put a muster counter on this enchantment. Then create a 1/1 red and white Soldier creature token with haste for each muster counter on this enchantment.

Wake the Past

Return all artifact cards from your graveyard to the battlefield. They gain haste until end of turn.

Valorous Stance

Choose one —
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
• Destroy target creature with toughness 4 or greater.

The Spear of Leonidas

Whenever equipped creature attacks, choose one —
• Bull Rush — It gains double strike until end of turn.
• Summon — Create Phobos, a legendary 3/2 red Horse creature token.
• Revelation — Discard two cards, then draw two cards.
Equip {2}

Plargg and Nassari

At the beginning of your upkeep, each player exiles cards from the top of their library until they exile a nonland card. An opponent chooses a nonland card exiled this way. You may cast up to two spells from among the other cards exiled this way without paying their mana costs.

Arbaaz Mir

Whenever Arbaaz Mir or another nontoken historic permanent you control enters, Arbaaz Mir deals 1 damage to each opponent and you gain 1 life. (Artifacts, legendaries, and Sagas are historic.)

Gimli, Counter of Kills

Trample
Whenever a creature an opponent controls dies, Gimli deals 1 damage to that creature's controller.

The Reaver Cleaver

Equipped creature gets +1/+1 and has trample and "Whenever this creature deals combat damage to a player or planeswalker, create that many Treasure tokens."
Equip {3}

Spirit Link

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Whenever enchanted creature deals damage, you gain that much life.

Baird, Argivian Recruiter

At the beginning of your end step, if you control a creature with power greater than its base power, create a 1/1 white Soldier creature token.

Monastery Raid

Freerunning {X}{R} (You may cast this spell for its freerunning cost if you dealt combat damage to a player this turn with an Assassin or commander.)
Exile the top two cards of your library. If this spell's freerunning cost was paid, exile the top X cards of your library instead. You may play the exiled cards until the end of your next turn.

Lightning Strike

Lightning Strike deals 3 damage to any target.

Aya of Alexandria

Menace, lifelink
Whenever a historic creature you control deals combat damage to a player, create a 1/1 black Assassin creature token with menace. (Artifacts, legendaries, and Sagas are historic.)

Hidden Footblade

Flash
When this Equipment enters, attach it to target creature you control. That creature gains first strike until end of turn.
Equipped creature gets +1/+0 and has haste.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Origin of the Hidden Ones

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga deals 4 damage to any target.
II — Create two 1/1 black Assassin creature tokens with menace.
III — Whenever an Assassin you control attacks this turn, create a 1/1 black Assassin creature token with menace that's tapped and attacking.

Unfinished Business

Return target creature card from your graveyard to the battlefield, then return up to two target Aura and/or Equipment cards from your graveyard to the battlefield attached to that creature. (If the Auras can't enchant that creature, they remain in your graveyard.)

Solar Blast

Solar Blast deals 3 damage to any target.
Cycling {1}{R}{R} ({1}{R}{R}, Discard this card: Draw a card.)
When you cycle this card, you may have it deal 1 damage to any target.

Excalibur, Sword of Eden

This spell costs {X} less to cast, where X is the total mana value of historic permanents you control. (Artifacts, legendaries, and Sagas are historic.)
Equipped creature gets +10/+0 and has vigilance.
Equip legendary creature {2}

Bill the Pony

When Bill the Pony enters, create two Food tokens. (They're artifacts with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Sacrifice a Food: Until end of turn, target creature you control assigns combat damage equal to its toughness rather than its power.

Flame-Blessed Bolt

Flame-Blessed Bolt deals 2 damage to target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.

Terramorphic Expanse

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

Tatsumasa, the Dragon's Fang

Equipped creature gets +5/+5.
{6}, Exile Tatsumasa: Create a 5/5 blue Dragon Spirit creature token with flying. Return Tatsumasa to the battlefield under its owner's control when that token dies.
Equip {3}

Sol Ring

Boros Signet

Wayfarer's Bauble

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

Cathartic Reunion

As an additional cost to cast this spell, discard two cards.
Draw three cards.

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Hurloon Battle Hymn

Kicker {W} (You may pay an additional {W} as you cast this spell.)
Hurloon Battle Hymn deals 4 damage to target creature or planeswalker. If this spell was kicked, you gain 4 life.

Brotherhood Headquarters

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast an Assassin spell or a spell that has freerunning, or to activate an ability of an Assassin source.

Mystic Forge

You may look at the top card of your library any time.
You may cast artifact spells and colorless spells from the top of your library.
{T}, Pay 1 life: Exile the top card of your library.

Barbarian Ring

{T}: Add {R}. This land deals 1 damage to you.
Threshold — {R}, {T}, Sacrifice this land: It deals 2 damage to any target. Activate only if seven or more cards are in your graveyard.

Daring Discovery

Up to three target creatures can't block this turn.
Discover 4. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)