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.)

Omniscience

You may cast spells from your hand without paying their mana costs.

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Papalymo Totolymo

Whenever you cast a noncreature spell, Papalymo Totolymo deals 1 damage to each opponent and you gain 1 life.
{4}, {T}, Sacrifice Papalymo Totolymo: Each opponent who lost life this turn sacrifices a creature with the greatest power among creatures they control.

Phyrexian Obliterator

Trample
Whenever a source deals damage to this creature, that source's controller sacrifices that many permanents of their choice.

Mnemonic Betrayal

Exile all opponents' graveyards. You may cast spells from among those cards this turn, and mana of any type can be spent to cast them. At the beginning of the next end step, if any of those cards remain exiled, return them to their owners' graveyards.
Exile Mnemonic Betrayal.

Y'shtola, Night's Blessed

Vigilance
At the beginning of each end step, if a player lost 4 or more life this turn, you draw a card.
Whenever you cast a noncreature spell with mana value 3 or greater, Y'shtola deals 2 damage to each opponent and you gain 2 life.

Swamp

The Darkness Crystal

Black spells you cast cost {1} less to cast.
If a nontoken creature an opponent controls would die, instead exile it and you gain 2 life.
{4}{B}{B}, {T}: Put target creature card exiled with The Darkness Crystal onto the battlefield tapped under your control with two additional +1/+1 counters on it.

Ajani Goldmane

+1: You gain 2 life.
−1: Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.
−6: Create a white Avatar creature token. It has "This token's power and toughness are each equal to your life total."

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have this creature enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Skyship Weatherlight

When Skyship Weatherlight enters, search your library for any number of artifact and/or creature cards, exile them, then shuffle.
{4}, {T}: Choose a card at random that was exiled with Skyship Weatherlight. Put that card into its owner's hand.

Norn's Annex

({W/P} can be paid with either {W} or 2 life.)
Creatures can't attack you or planeswalkers you control unless their controller pays {W/P} for each of those creatures.

Hall of Heliod's Generosity

{T}: Add {C}.
{1}{W}, {T}: Put target enchantment card from your graveyard on top of your library.

Healer of the Pride

Whenever another creature you control enters, you gain 2 life.

Congregate

Target player gains 2 life for each creature on the battlefield.

Wound Reflection

At the beginning of each end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Polluted Bonds

Whenever a land an opponent controls enters, that player loses 2 life and you gain 2 life.

Raksha Golden Cub

Vigilance
As long as Raksha Golden Cub is equipped, Cat creatures you control get +2/+2 and have double strike.

Black Market

Whenever a creature dies, put a charge counter on this enchantment.
At the beginning of your first main phase, add {B} for each charge counter on this enchantment.

Three Tree City

As Three Tree City enters, choose a creature type.
{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is this creature's power.

Adaptive Omnitool

Equipped creature gets +1/+1 for each artifact you control.
Whenever equipped creature attacks, look at the top six cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Equip {3}

Sol Ring

Darksteel Forge

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Scrawling Crawler

At the beginning of your upkeep, each player draws a card.
Whenever an opponent draws a card, that player loses 1 life.

Plains

Elesh Norn, Mother of Machines

Vigilance
If a permanent entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Permanents entering don't cause abilities of permanents your opponents control to trigger.

Promise of Loyalty

Each player puts a vow counter on a creature they control and sacrifices the rest. Each of those creatures can't attack you or planeswalkers you control for as long as it has a vow counter on it.

Urza, Lord High Artificer

When Urza enters, create a 0/0 colorless Construct artifact creature token with "This token gets +1/+1 for each artifact you control."
Tap an untapped artifact you control: Add {U}.
{5}: Shuffle your library, then exile the top card. Until end of turn, you may play that card without paying its mana cost.

Ardbert, Warrior of Darkness

Whenever you cast a white spell, put a +1/+1 counter on each legendary creature you control. They gain vigilance until end of turn.
Whenever you cast a black spell, put a +1/+1 counter on each legendary creature you control. They gain menace until end of turn.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Undermine

Counter target spell. Its controller loses 3 life.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Diabolic Revelation

Search your library for up to X cards, put those cards into your hand, then shuffle.

Mycosynth Lattice

All permanents are artifacts in addition to their other types.
All cards that aren't on the battlefield, spells, and permanents are colorless.
Players may spend mana as though it were mana of any color.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: This artifact deals 50 damage to any target.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Absorb

Krile Baldesion

Lifelink
Trace Aether — Whenever you cast a noncreature spell, you may return target creature card with mana value equal to that spell's mana value from your graveyard to your hand. Do this only once each turn.

Sanguine Bond

Whenever you gain life, target opponent loses that much life.

Debt to the Deathless

Each opponent loses two times X life. You gain life equal to the life lost this way.

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Sheoldred, the Apocalypse

Deathtouch
Whenever you draw a card, you gain 2 life.
Whenever an opponent draws a card, they lose 2 life.

Crystal Barricade

Defender (This creature can't attack.)
You have hexproof. (You can't be the target of spells or abilities your opponents control.)
Prevent all noncombat damage that would be dealt to other creatures you control.

Ghostly Prison

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Leonin Abunas

Artifacts you control have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Land Tax

At the beginning of your upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter tapped.

Render Silent

Counter target spell. Its controller can't cast spells this turn.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.

Authority of the Consuls

Creatures your opponents control enter tapped.
Whenever a creature an opponent controls enters, you gain 1 life.

Counterspell

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Leonin Elder

Whenever an artifact enters, you may gain 1 life.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Basilisk Collar

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

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.

Rakshasa Debaser

Whenever this creature attacks, put target creature card from defending player's graveyard onto the battlefield under your control.
Encore {6}{B}{B} ({6}{B}{B}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Enduring Curiosity

Flash
Whenever a creature you control deals combat damage to a player, draw a card.
When Enduring Curiosity dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

Nevinyrral's Disk

This artifact enters tapped.
{1}, {T}: Destroy all artifacts, creatures, and enchantments.

Reliquary Tower

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

Elesh Norn, Grand Cenobite

Vigilance
Other creatures you control get +2/+2.
Creatures your opponents control get -2/-2.

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Kambal, Consul of Allocation

Whenever an opponent casts a noncreature spell, that player loses 2 life and you gain 2 life.

Island

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)