Stronghold Biologist

{U}{U}, {T}, Discard a card: Counter target creature spell.

Tribute to Hunger

Target opponent sacrifices a creature of their choice. You gain life equal to that creature's toughness.

Blood Baron of Vizkopa

Lifelink, protection from white and from black
As long as you have 30 or more life and an opponent has 10 or less life, Blood Baron of Vizkopa gets +6/+6 and has flying.

Tasigur, the Golden Fang

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
{2}{G/U}{G/U}: Mill two cards, then return a nonland card of an opponent's choice from your graveyard to your hand.

Insidious Mist

Hexproof, indestructible
Insidious Mist can't block and can't be blocked.
Whenever Insidious Mist attacks and isn't blocked, you may pay {2}{B}. If you do, transform it.

Elusive Tormentor

{1}, Discard a card: Transform Elusive Tormentor.

Elusive Tormentor // Insidious Mist

Kongming, "Sleeping Dragon"

Teysa, Envoy of Ghosts

Vigilance, protection from creatures
Whenever a creature deals combat damage to you, destroy that creature. Create a 1/1 white and black Spirit creature token with flying.

Twisted Justice

Target player sacrifices a creature of their choice. You draw cards equal to that creature's power.

Mountain

Vedalken Plotter

When Vedalken Plotter enters, exchange control of target land you control and target land an opponent controls.

Spirit of the Labyrinth

Each player can't draw more than one card each turn.

Soldevi Sage

{T}, Sacrifice two lands: Draw three cards, then discard one of them.

Sigil of the Empty Throne

Whenever you cast an enchantment spell, create a 4/4 white Angel creature token with flying.

Gonti's Machinations

Whenever you lose life for the first time each turn, you get {E}. (You get an energy counter. Damage causes loss of life.)
Pay {E}{E}, Sacrifice Gonti's Machinations: Each opponent loses 3 life. You gain life equal to the life lost this way.

Kyren Negotiations

Tap an untapped creature you control: Kyren Negotiations deals 1 damage to target player or planeswalker.

Ampryn Tactician

When Ampryn Tactician enters, creatures you control get +1/+1 until end of turn.

Hand of Justice

{T}, Tap three untapped white creatures you control: Destroy target creature.

Markov Patrician

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Dragon Throne of Tarkir

Equipped creature has defender and "{2}, {T}: Other creatures you control gain trample and get +X/+X until end of turn, where X is this creature's power."
Equip {3}

High Priest of Penance

Whenever High Priest of Penance is dealt damage, you may destroy target nonland permanent.

Maze Sentinel

Vigilance
Multicolored creatures you control have vigilance.

Atogatog

Sacrifice an Atog creature: Atogatog gets +X/+X until end of turn, where X is the sacrificed creature's power.

Throne of Geth

{T}, Sacrifice an artifact: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Bargaining Table

{X}, {T}: Draw a card. X is the number of cards in an opponent's hand.

Cabal Patriarch

{2}{B}, Sacrifice a creature: Target creature gets -2/-2 until end of turn.
{2}{B}, Exile a creature card from your graveyard: Target creature gets -2/-2 until end of turn.

Knighthood

Stronghold Machinist

{U}{U}, {T}, Discard a card: Counter target noncreature spell.

Sands of Delirium

Vampire Noble

Devour Flesh

Target player sacrifices a creature of their choice, then gains life equal to that creature's toughness.

Void

Choose a number. Destroy all artifacts and creatures with mana value equal to that number. Then target player reveals their hand and discards all nonland cards with mana value equal to the number.

Murder

Keeper of Tresserhorn

Whenever Keeper of Tresserhorn attacks and isn't blocked, it assigns no combat damage this turn and defending player loses 2 life.

King Macar, the Gold-Cursed

Inspired — Whenever King Macar, the Gold-Cursed becomes untapped, you may exile target creature. If you do, create a Gold token. (It's an artifact with "Sacrifice this artifact: Add one mana of any color.")

Déjà Vu

Return target sorcery card from your graveyard to your hand.

Ghoulflesh

Enchant creature
Enchanted creature gets -1/-1 and is a black Zombie in addition to its other colors and types.

Cruel Edict

Target opponent sacrifices a creature of their choice.

Plains

Midnight Entourage

Other Aetherborn you control get +1/+1.
Whenever Midnight Entourage or another Aetherborn you control dies, you draw a card and you lose 1 life.

Dark Tutelage

At the beginning of your upkeep, reveal the top card of your library and put that card into your hand. You lose life equal to its mana value.

Driver of the Dead

When this creature dies, return target creature card with mana value 2 or less from your graveyard to the battlefield.

Swamp

Flash of Insight

Look at the top X cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
Flashback—{1}{U}, Exile X blue cards from your graveyard. (You may cast this card from your graveyard for its flashback cost, then exile it. You can't exile Flash of Insight to pay for its own flashback cost.)

Council of the Absolute

As Council of the Absolute enters, choose a noncreature, nonland card name.
Your opponents can't cast spells with the chosen name.
Spells with the chosen name you cast cost {2} less to cast.

Maw of the Obzedat

Sacrifice a creature: Creatures you control get +1/+1 until end of turn.

Throne of Bone

Whenever a player casts a black spell, you may pay {1}. If you do, you gain 1 life.

Hythonia the Cruel

Deathtouch
{6}{B}{B}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
When Hythonia the Cruel becomes monstrous, destroy all non-Gorgon creatures.

Architects of Will

When Architects of Will enters, look at the top three cards of target player's library, then put them back in any order.
Cycling {U/B} ({U/B}, Discard this card: Draw a card.)

Jalira, Master Polymorphist

{2}{U}, {T}, Sacrifice another creature: Reveal cards from the top of your library until you reveal a nonlegendary creature card. Put that card onto the battlefield and the rest on the bottom of your library in a random order.

Throne of Empires

{1}, {T}: Create a 1/1 white Soldier creature token. Create five of those tokens instead if you control artifacts named Crown of Empires and Scepter of Empires.

Vampire Warlord

Sacrifice another creature: Regenerate Vampire Warlord. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Order of Succession

Choose left or right. Starting with you and proceeding in the chosen direction, each player chooses a creature controlled by the next player in that direction. Each player gains control of the creature they chose.

Tithe Drinker

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
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.)

Blood Tithe

Each opponent loses 3 life. You gain life equal to the life lost this way.

Famine

Famine deals 3 damage to each creature and each player.

Sanctimony

Whenever an opponent taps a Mountain for mana, you may gain 1 life.

Contemplation

Whenever you cast a spell, you gain 1 life.

Military Intelligence

Whenever you attack with two or more creatures, draw a card.

Arcades Sabboth

Flying
At the beginning of your upkeep, sacrifice Arcades Sabboth unless you pay {G}{W}{U}.
Each untapped creature you control gets +0/+2 as long as it's not attacking.
{W}: Arcades Sabboth gets +0/+1 until end of turn.

Fall of the Gavel

Sorceress Queen

{T}: Target creature other than Sorceress Queen has base power and toughness 0/2 until end of turn.

Blood Host

{1}{B}, Sacrifice another creature: Put a +1/+1 counter on Blood Host and you gain 2 life.

Vampire Sovereign

Flying
When Vampire Sovereign enters, target opponent loses 3 life and you gain 3 life.