Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Sol Ring

Scrying Sheets

{T}: Add {C}.
{1}{S}, {T}: Look at the top card of your library. If that card is snow, you may reveal it and put it into your hand. ({S} can be paid with one mana from a snow source.)

Nim Deathmantle

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay {4}. If you do, return that card to the battlefield and attach Nim Deathmantle to it.
Equip {4}

Clone Shell

Imprint — When Clone Shell enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom of your library in any order.
When Clone Shell dies, turn the exiled card face up. If it's a creature card, put it onto the battlefield under your control.

Rimescale Dragon

Flying
{2}{S}: Tap target creature and put an ice counter on it. ({S} can be paid with one mana from a snow source.)
Creatures with ice counters on them don't untap during their controllers' untap steps.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Glacial Crevasses

Sacrifice a snow Mountain: Prevent all combat damage that would be dealt this turn.

Sandstone Needle

Sandstone Needle enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Sandstone Needle: Add {R}{R}. If there are no depletion counters on Sandstone Needle, sacrifice it.

Word of Seizing

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Untap target permanent and gain control of it until end of turn. It gains haste until end of turn.

Molten Primordial

Haste
When Molten Primordial enters, for each opponent, gain control of up to one target creature that player controls until end of turn. Untap those creatures. They gain haste until end of turn.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Homeward Path

{T}: Add {C}.
{T}: Each player gains control of all creatures they own.

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Bazaar Trader

{T}: Target player gains control of target artifact, creature, or land you control.

Thousand-Year Elixir

You may activate abilities of creatures you control as though those creatures had haste.
{1}, {T}: Untap target creature.

Conquering Manticore

Flying
When Conquering Manticore enters, gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn.

Miren, the Moaning Well

{T}: Add {C}.
{3}, {T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

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."

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

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.

Insurrection

Untap all creatures and gain control of them until end of turn. They gain haste until end of turn.

Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Helm of Possession

You may choose not to untap Helm of Possession during your untap step.
{2}, {T}, Sacrifice a creature: Gain control of target creature for as long as you control Helm of Possession and Helm of Possession remains tapped.

Duplicant

Imprint — When Duplicant enters, you may exile target nontoken creature.
As long as a card exiled with Duplicant is a creature card, Duplicant has the power, toughness, and creature types of the last creature card exiled with Duplicant. It's still a Shapeshifter.

Wurmcoil Engine

Deathtouch, lifelink
When Wurmcoil Engine dies, create a 3/3 colorless Phyrexian Wurm artifact creature token with deathtouch and a 3/3 colorless Phyrexian Wurm artifact creature token with lifelink.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Gilded Lotus

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

Darksteel Citadel

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Homura's Essence

Creatures you control get +2/+2 and have flying and "{R}: This creature gets +1/+0 until end of turn."

Homura, Human Ascendant

Homura, Human Ascendant can't block.
When Homura dies, return it to the battlefield flipped.

Homura, Human Ascendant // Homura's Essence

Sneak Attack

{R}: You may put a creature card from your hand onto the battlefield. That creature gains haste. Sacrifice the creature at the beginning of the next end step.

Pilgrim's Eye

Flying
When Pilgrim's Eye enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Expedition Map

{2}, {T}, Sacrifice this artifact: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Inferno Titan

{R}: Inferno Titan gets +1/+0 until end of turn.
Whenever Inferno Titan enters or attacks, it deals 3 damage divided as you choose among one, two, or three targets.

Starke of Rath

{T}: Destroy target artifact or creature. That permanent's controller gains control of Starke of Rath. (This effect lasts indefinitely.)

Reforge the Soul

Each player discards their hand, then draws seven cards.
Miracle {1}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Reliquary Tower

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

Dockside Extortionist

When Dockside Extortionist enters, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Kari Zev's Expertise

Gain control of target creature or Vehicle until end of turn. Untap it. It gains haste until end of turn.
You may cast a spell with mana value 2 or less from your hand without paying its mana cost.

Starstorm

Starstorm deals X damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Darksteel Pendant

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{1}, {T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Claim the Firstborn

Gain control of target creature with mana value 3 or less until end of turn. Untap that creature. It gains haste until end of turn.

Magewright's Stone

{1}, {T}: Untap target creature that has an activated ability with {T} in its cost.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Heart of Ramos

{T}: Add {R}.
Sacrifice Heart of Ramos: Add {R}.

Erratic Portal

{1}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Dire Fleet Daredevil

First strike
When Dire Fleet Daredevil enters, exile target instant or sorcery card from an opponent's graveyard. You may cast it this turn, and mana of any type can be spent to cast that spell. If that spell would be put into a graveyard, exile it instead.

Planar Portal

{6}, {T}: Search your library for a card, put that card into your hand, then shuffle.

Flametongue Kavu

When Flametongue Kavu enters, it deals 4 damage to target creature.

Mind Stone

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

Snow-Covered Mountain

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Thran Dynamo

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

Scarecrone

{1}, Sacrifice a Scarecrow: Draw a card.
{4}, {T}: Return target artifact creature card from your graveyard to the battlefield.

Forgotten Cave

Forgotten Cave enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Zealous Conscripts

Haste
When Zealous Conscripts enters, gain control of target permanent until end of turn. Untap that permanent. It gains haste until end of turn.

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Ruby Medallion

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

Mind's Eye

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Kiki-Jiki, Mirror Breaker

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

Valakut Stoneforge

Valakut Stoneforge enters tapped.
{T}: Add {R}.

Valakut Awakening

Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Valakut Awakening // Valakut Stoneforge

Fissure

Destroy target creature or land. It can't be regenerated.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Leyline of Punishment

If Leyline of Punishment is in your opening hand, you may begin the game with it on the battlefield.
Players can't gain life.
Damage can't be prevented.