Arc Runner

Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice Arc Runner.

Scuttling Butler

At the beginning of combat on your turn, if you control two or more multicolored permanents, Scuttling Butler gains double strike until end of turn.

Blistering Barrier

Frost Walker

When Frost Walker becomes the target of a spell or ability, sacrifice it.

Mijae Djinn

Whenever Mijae Djinn attacks, flip a coin. If you lose the flip, remove Mijae Djinn from combat and tap it.

Ashcloud Phoenix

Flying
When Ashcloud Phoenix dies, return it to the battlefield face down under your control.
Morph {4}{R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Ashcloud Phoenix is turned face up, it deals 2 damage to each player.

Phyrexian Soulgorger

Cumulative upkeep—Sacrifice a creature. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Ruinous Minotaur

Whenever Ruinous Minotaur deals damage to an opponent, sacrifice a land.

Okk can't attack unless a creature with greater power also attacks.
Okk can't block unless a creature with greater power also blocks.

Lupine Prototype

Lupine Prototype can't attack or block unless a player has no cards in hand.

Blistering Firecat

Trample, haste
At the beginning of the end step, sacrifice Blistering Firecat.
Morph {R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Phantasmal Abomination

Defender
When Phantasmal Abomination becomes the target of a spell or ability, sacrifice it.

Dreamtide Whale

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a player casts their second spell each turn, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Relic Golem

Relic Golem can't attack or block unless an opponent has eight or more cards in their graveyard.
{2}, {T}: Target player mills two cards. (They put the top two cards of their library into their graveyard.)

Kylox, Visionary Inventor

Menace, ward {2}, haste
Whenever Kylox, Visionary Inventor attacks, sacrifice any number of other creatures, then exile the top X cards of your library, where X is their total power. You may cast any number of instant and/or sorcery spells from among the exiled cards without paying their mana costs.

Goblin Goon

Goblin Goon can't attack unless you control more creatures than defending player.
Goblin Goon can't block unless you control more creatures than attacking player.

Imaginary Pet

At the beginning of your upkeep, if you have a card in hand, return Imaginary Pet to its owner's hand.

Big Winner

Big Winner has trample as long as you control a stickered permanent.

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Keldon Vandals

Echo {2}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Keldon Vandals enters, destroy target artifact.

Cosmic Larva

Trample
At the beginning of your upkeep, sacrifice Cosmic Larva unless you sacrifice two lands.