Shard of the Nightbringer

Flying
Drain Life — When Shard of the Nightbringer enters the battlefield, if you cast it, target opponent loses half their life, rounded up. You gain life equal to the life lost this way.

Sanguine Bond

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

Raffine, Scheming Seer

Flying, ward {1}
Whenever you attack, target attacking creature connives X, where X is the number of attacking creatures. (Draw X cards, then discard X cards. Put a +1/+1 counter on that creature for each nonland card discarded this way.)

Arcane Sanctum

Arcane Sanctum enters the battlefield tapped.
{T}: Add {W}, {U}, or {B}.

Shorikai, Genesis Engine

{1}, {T}: Draw two cards, then discard a card. Create a 1/1 colorless Pilot creature token with "This creature 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.)
Shorikai, Genesis Engine can be your commander.

Exotic Orchard

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

Command Tower

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

Debt to the Deathless

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

Queza, Augur of Agonies

Whenever you draw a card, target opponent loses 1 life and you gain 1 life.

Curry Favor

You gain X life and each opponent loses X life, where X is the number of Knights you control.

Smitten Swordmaster

Smitten Swordmaster // Curry Favor

Glacial Fortress

Glacial Fortress enters the battlefield tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Plains

Lonely Arroyo

Lonely Arroyo enters the battlefield tapped.
When Lonely Arroyo enters the battlefield, it deals 1 damage to target opponent.
{T}: Add {W} or {U}.

Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Astarion, the Decadent

Deathtouch, lifelink
At the beginning of your end step, choose one —
• Feed — Target opponent loses life equal to the amount of life they lost this turn.
• Friends — You gain life equal to the amount of life you gained this turn.

Island

Commander's Sphere

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

Traverse Eternity

Draw cards equal to the highest mana value among historic permanents you control. (Artifacts, legendaries, and Sagas are historic.)

Mind Stone

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

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

Foul-Tongue Shriek

Target opponent loses 1 life for each attacking creature you control. You gain that much life.

Starscape Cleric

Offspring {2}{B} (You may pay an additional {2}{B} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Flying
This creature can't block.
Whenever you gain life, each opponent loses 1 life.

Campaign of Vengeance

Whenever a creature you control attacks, defending player loses 1 life and you gain 1 life.

Drogskol Reaver

Flying, double strike, lifelink
Whenever you gain life, draw a card.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Gilded Lotus

Damnable Pact

Target player draws X cards and loses X life.

Knights' Charge

Whenever a Knight you control attacks, each opponent loses 1 life and you gain 1 life.
{6}{W}{B}, Sacrifice Knights' Charge: Return all Knight creature cards from your graveyard to the battlefield.

Restless Fortress

Restless Fortress enters the battlefield tapped.
{T}: Add {W} or {B}.
{2}{W}{B}: Restless Fortress becomes a 1/4 white and black Nightmare creature until end of turn. It's still a land.
Whenever Restless Fortress attacks, defending player loses 2 life and you gain 2 life.

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Fellwar Stone

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Dimir Signet

Elenda's Hierophant

Flying
Whenever you gain life, put a +1/+1 counter on Elenda's Hierophant.
When Elenda's Hierophant dies, create X 1/1 white Vampire creature tokens with lifelink, where X is its power.

Locus of Enlightenment

Locus of Enlightenment has each activated ability of the exiled cards used to craft it. You may activate each of those abilities only once each turn.
Whenever you activate an ability that isn't a mana ability, copy it. You may choose new targets for the copy.

The Enigma Jewel

The Enigma Jewel enters the battlefield tapped.
{T}: Add {C}{C}. Spend this mana only to activate abilities.
Craft with four or more nonlands with activated abilities {8}{U} ({8}{U}, Exile this artifact, Exile the four or more from among other permanents you control and/or cards in your graveyard: Return this card transformed under its owner's control. Craft only as a sorcery.)

The Enigma Jewel // Locus of Enlightenment

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Azorius Signet

Peer into the Abyss

Target player draws cards equal to half the number of cards in their library and loses half their life. Round up each time.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Arcane Signet

Champion of Dusk

When Champion of Dusk enters the battlefield, you draw X cards and you lose X life, where X is the number of Vampires you control.

Brotherhood Regalia

Equipped creature has ward {2}, is an Assassin in addition to its other types, and can't be blocked.
Equip legendary creature {1}
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Herald of Hoofbeats

Horsemanship (This creature can't be blocked except by creatures with horsemanship.)
Other Knights you control have horsemanship.

Skycloud Expanse

Thought Vessel

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

Death Grasp

Death Grasp deals X damage to any target. You gain X life.

Soured Springs

Soured Springs enters the battlefield tapped.
When Soured Springs enters the battlefield, it deals 1 damage to target opponent.
{T}: Add {U} or {B}.

Gruesome Fate

Each opponent loses 1 life for each creature you control.

Orzhov Signet

Worn Powerstone

Worn Powerstone enters the battlefield tapped.
{T}: Add {C}{C}.

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters the battlefield tapped unless you control two or more basic lands.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Elenda and Azor

Flying, ward {2}
Whenever Elenda and Azor attacks, you may pay {X}{W}{U}{B}. If you do, draw X cards.
At the beginning of each end step, you may pay 4 life. If you do, create a number of 1/1 black Vampire Knight creature tokens with lifelink equal to the number of cards you've drawn this turn.

Forlorn Flats

Forlorn Flats enters the battlefield tapped.
When Forlorn Flats enters the battlefield, it deals 1 damage to target opponent.
{T}: Add {W} or {B}.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Exsanguinate

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

Talisman of Progress

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

Cliffhaven Vampire

Flying
Whenever you gain life, each opponent loses 1 life.

Sol Ring

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters the battlefield tapped unless you control two or more basic lands.

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters the battlefield with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.

Pull from Tomorrow

Voldaren Estate

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Spend this mana only to cast a Vampire spell.
{5}, {T}: Create a Blood token. This ability costs {1} less to activate for each Vampire you control. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Thran Dynamo

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Malakir Bloodwitch

Flying, protection from white
When Malakir Bloodwitch enters the battlefield, each opponent loses life equal to the number of Vampires you control. You gain life equal to the life lost this way.

Darkwater Catacombs

Skemfar Shadowsage

When Skemfar Shadowsage enters the battlefield, choose one —
• Each opponent loses X life, where X is the greatest number of creatures you control that have a creature type in common.
• You gain X life, where X is the greatest number of creatures you control that have a creature type in common.

Talisman of Hierarchy

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

Swamp

Corpse Knight

Whenever another creature enters the battlefield under your control, each opponent loses 1 life.

Krav, the Unredeemed

Partner with Regna, the Redeemer (When this creature enters the battlefield, target player may put Regna into their hand from their library, then shuffle.)
{B}, Sacrifice X creatures: Target player draws X cards and gains X life. Put X +1/+1 counters on Krav, the Unredeemed.

Wispdrinker Vampire

Flying
Whenever another creature with power 2 or less enters the battlefield under your control, each opponent loses 1 life and you gain 1 life.
{5}{W}{B}: Creatures you control with power 2 or less gain deathtouch and lifelink until end of turn.

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Sol Talisman

Suspend 3—{1} (Rather than cast this card from your hand, pay {1} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add {C}{C}.

Sphinx of the Revelation

Flying, lifelink
Whenever you gain life, you get that many {E} (energy counters).
{W}{U}{U}, {T}, Pay X {E}: Draw X cards.

Vodalian Wave-Knight

Whenever you draw a card, put a +1/+1 counter on each other Merfolk and/or Knight you control.

Sanctum Seeker

Whenever a Vampire you control attacks, each opponent loses 1 life and you gain 1 life.

Ayara, First of Locthwain

Whenever Ayara, First of Locthwain or another black creature enters the battlefield under your control, each opponent loses 1 life and you gain 1 life.
{T}, Sacrifice another black creature: Draw a card.

Vizkopa Guildmage

{1}{W}{B}: Target creature gains lifelink until end of turn.
{1}{W}{B}: Whenever you gain life this turn, each opponent loses that much life.

Elas il-Kor, Sadistic Pilgrim

Deathtouch
Whenever another creature enters the battlefield under your control, you gain 1 life.
Whenever another creature you control dies, each opponent loses 1 life.