You may have Auton Soldier enter the battlefield as a copy of any creature on the battlefield, except it isn't legendary, is an artifact in addition to its other types, and has myriad. (Whenever it attacks, for each opponent other than defending player, you may put a token that's a copy of this creature onto the battlefield tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Flying

Protection from red (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything red.)

Sacrifice Cerulean Drake: Counter target spell that targets you.

Whenever Cordial Vampire or another creature dies, put a +1/+1 counter on each Vampire you control.

Indestructible

Whenever Creepy Doll deals combat damage to a creature, flip a coin. If you win the flip, destroy that creature.

Flying

Whenever you cast a noncreature spell, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Return target nonland permanent you don't control to its owner's hand.

Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

When Disciple of Bolas enters the battlefield, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.

Menace

{1}{B}, Sacrifice Dusk Legion Sergeant: Each nontoken Vampire creature you control gains persist until end of turn. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Exile target creature or planeswalker. Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Flying, deathtouch

Embodiment of Agonies enters the battlefield with a +1/+1 counter on it for each different mana cost among nonland cards in your graveyard. (For example, {2}{B} and {1}{B}{B} are different mana costs.)

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Enchant creature

Enchanted creature gets +2/+2 as long as it's a Vampire. Otherwise, it gets -2/-2.

Sacrifice Hapless Researcher: Draw a card, then discard a card.

Flying

At the beginning of combat on your turn, choose one that hasn't been chosen --

• Each player sacrifices a creature.

• You draw a card and you lose 1 life.

• Transform Henrika Domnathi.

Flying, deathtouch, lifelink

{1}{B}{B}: Each creature you control with flying, deathtouch, and/or lifelink gets +1/+0 until end of turn.

Lifelink

{2}, Sacrifice a creature: Put a +1/+1 counter on each Vampire you control.

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)

When Invasion of Amonkhet enters the battlefield, each player mills three cards, then each opponent discards a card and you draw a card. (To mill three cards, a player puts the top three cards of their library into their graveyard.)

You may have Lazotep Convert enter the battlefield as a copy of any creature card in a graveyard, except it's a 4/4 black Zombie in addition to its other colors and types.

At the beginning of your end step, if Kaito Shizuki entered the battlefield this turn, he phases out.

+1: Draw a card. Then discard a card unless you attacked this turn.

-2: Create a 1/1 blue Ninja creature token with "This creature can't be blocked."

-7: You get an emblem with "Whenever a creature you control deals combat damage to a player, search your library for a blue or black creature card, put it onto the battlefield, then shuffle."

Lifelink

If a nontoken creature an opponent controls would die, instead exile that card and create a 2/2 black Zombie creature token.

{2}{B}, Sacrifice another Vampire or Zombie: Put two +1/+1 counters on Kalitas, Traitor of Ghet.

Menace

Whenever you sacrifice a creature, you may pay {U/B}. If you do, draw a card. ({U/B} can be paid with either {U} or {B}.)

{1}, Sacrifice a creature: Kels, Fight Fixer gains indestructible until end of turn.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Destroy target creature or planeswalker. Each creature that convoked Lethal Scheme connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

{1}, Sacrifice Living Lectern: Draw a card. Create a Sorcerer Role token attached to up to one other target creature you control. Activate only as a sorcery. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has "Whenever this creature attacks, scry 1.")

Counter target noncreature spell.

Oathsworn Knight enters the battlefield with four +1/+1 counters on it.

Oathsworn Knight attacks each combat if able.

If damage would be dealt to Oathsworn Knight while it has a +1/+1 counter on it, prevent that damage and remove a +1/+1 counter from it.

{T}: Search your library for a card, put it into your graveyard, then shuffle. If it's an instant or sorcery card, put a +1/+1 counter on Oriq Loremage.

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

You may have Sakashima of a Thousand Faces enter the battlefield as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities.

The "legend rule" doesn't apply to permanents you control.

Partner (You can have two commanders if both have partner.)

You may have Sakashima the Impostor enter the battlefield as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."

Menace, lifelink

{1}, Sacrifice another creature: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

At the beginning of your end step, if there are five or more mana values among cards in your graveyard, you may pay 2 life. If you do, draw a card.

Menace (This creature can't be blocked except by two or more creatures.)

Whenever one or more artifacts and/or creatures you control are put into a graveyard from the battlefield, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

As an additional cost to cast this spell, discard a card or sacrifice a permanent.

Fathomless descent -- Souls of the Lost's power is equal to the number of permanent cards in your graveyard and its toughness is equal to that number plus 1.

You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Flying

Sacrifice Spiketail Drake: Counter target spell unless its controller pays {3}.

Flying

Sacrifice Spiketail Drakeling: Counter target spell unless its controller pays {2}.

Flying (This creature can't be blocked except by creatures with flying or reach.)

Sacrifice Spiketail Hatchling: Counter target spell unless its controller pays {1}.

Equipped creature has vigilance.

Whenever another artifact or creature is put into a graveyard from the battlefield, put a +1/+1 counter on equipped creature.

Equip {2}

Defender

Thing in the Ice enters the battlefield with four ice counters on it.

Whenever you cast an instant or sorcery spell, remove an ice counter from Thing in the Ice. Then if it has no ice counters on it, transform it.

When this creature transforms into Awoken Horror, return all non-Horror creatures to their owners' hands.

Counter target spell. Its controller loses 3 life.

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Return target creature card with mana value 3 or less from your graveyard to the battlefield.

Cycling {2} ({2}, Discard this card: Draw a card.)

Pay 3 life: Put a +1/+1 counter on target creature.

Target creature gets -3/-3 until end of turn. You may tap any number of untapped Vampire creatures you control. If you do, put a +1/+1 counter on each of those Vampires.

Descend 8 -- Choose one. If there are eight or more permanent cards in your graveyard as you cast this spell, choose one or more instead.

• Return target nonland permanent to its owner's hand.

• Target opponent discards a card.

• Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Haste

Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.

Sacrifice another creature: Yahenni gains indestructible until end of turn.