Ravenous Tyrannosaurus

Devour 3 (As this enters, you may sacrifice any number of creatures. This creature enters with three times that many +1/+1 counters on it.)
Whenever Ravenous Tyrannosaurus attacks, it deals damage equal to its power to up to one other target creature. Excess damage is dealt to that creature's controller instead.

Spider

Oko, the Ringleader

At the beginning of combat on your turn, Oko, the Ringleader becomes a copy of up to one target creature you control until end of turn, except he has hexproof.
+1: Draw two cards. If you've committed a crime this turn, discard a card. Otherwise, discard two cards.
−1: Create a 3/3 green Elk creature token.
−5: For each other nonland permanent you control, create a token that's a copy of that permanent.

Demon

Kokusho, the Evening Star

Flying
When Kokusho, the Evening Star dies, each opponent loses 5 life. You gain life equal to the life lost this way.

Tribute to the World Tree

Whenever a creature you control enters, draw a card if its power is 3 or greater. Otherwise, put two +1/+1 counters on it.

Disharmony

Cast this spell only during combat before blockers are declared.
Untap target attacking creature and remove it from combat. Gain control of that creature until end of turn.

Kalitas, Traitor of Ghet

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.

Goldvein Hydra

Vigilance, trample, haste
Goldvein Hydra enters with X +1/+1 counters on it.
When Goldvein Hydra dies, create a number of tapped Treasure tokens equal to its power.

Hydra

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Tezzeret, Master of the Bridge

Creature and planeswalker spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)
+2: Tezzeret, Master of the Bridge deals X damage to each opponent, where X is the number of artifacts you control. You gain X life.
−3: Return target artifact card from your graveyard to your hand.
−8: Exile the top ten cards of your library. Put all artifact cards from among them onto the battlefield.

Black Market Connections

At the beginning of your first main phase, choose one or more —
• Sell Contraband — Create a Treasure token. You lose 1 life.
• Buy Information — Draw a card. You lose 2 life.
• Hire a Mercenary — Create a 3/2 colorless Shapeshifter creature token with changeling. You lose 3 life. (It has every creature type.)

Hunting Velociraptor

First strike
Dinosaur spells you cast have prowl {2}{R}. (You may cast a spell for its prowl cost if you dealt combat damage to a player this turn with a creature with any of its creature types.)

Throne of the God-Pharaoh

At the beginning of your end step, each opponent loses life equal to the number of tapped creatures you control.

Ruthless Lawbringer

When Ruthless Lawbringer enters, you may sacrifice another creature. When you do, destroy target nonland permanent.

Sword of the Realms

Equipped creature gets +2/+0 and has vigilance.
Whenever equipped creature dies, return it to its owner's hand.
Equip {1}{W}

Halvar, God of Battle

Creatures you control that are enchanted or equipped have double strike.
At the beginning of each combat, you may attach target Aura or Equipment attached to a creature you control to target creature you control.

Halvar, God of Battle // Sword of the Realms

Mana Tithe

Counter target spell unless its controller pays {1}.

Zodiac Dragon

When Zodiac Dragon is put into your graveyard from the battlefield, you may return it to your hand.

Delayed Blast Fireball

Delayed Blast Fireball deals 2 damage to each opponent and each creature they control. If this spell was cast from exile, it deals 5 damage to each opponent and each creature they control instead.
Foretell {4}{R}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Thopter

Eldrazi

Comet, Stellar Pup

0: Roll a six-sided die.
1 or 2 — [+2], then create two 1/1 green Squirrel creature tokens. They gain haste until end of turn.
3 — [−1], then return a card with mana value 2 or less from your graveyard to your hand.
4 or 5 — Comet, Stellar Pup deals damage equal to the number of loyalty counters on him to a creature or player, then [−2].
6 — [+1], and you may activate Comet, Stellar Pup's loyalty ability two more times this turn.

Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Goblin

Sliver

Goblin General

Whenever Goblin General attacks, Goblin creatures you control get +1/+1 until end of turn.

Thorncaster Sliver

Sliver creatures you control have "Whenever this creature attacks, it deals 1 damage to any target."

Vampire

Dinosaurs on a Spaceship

Vigilance, trample
Other Dinosaurs you control get +1/+1 and have vigilance and trample.
Suspend 4—{3}{R}{W}
Whenever a time counter is removed from Dinosaurs on a Spaceship while it's exiled, create a 2/2 red and white Dinosaur creature token with flying and haste.

Sorin, Imperious Bloodlord

+1: Target creature you control gains deathtouch and lifelink until end of turn. If it's a Vampire, put a +1/+1 counter on it.
+1: You may sacrifice a Vampire. When you do, Sorin, Imperious Bloodlord deals 3 damage to any target and you gain 3 life.
−3: You may put a Vampire creature card from your hand onto the battlefield.

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Rakdos, Patron of Chaos

Flying, trample
At the beginning of your end step, target opponent may sacrifice two nonland, nontoken permanents of their choice. If they don't, you draw two cards.

Saproling

Essence Sliver

Whenever a Sliver deals damage, its controller gains that much life.

Relentless Assault

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Vaultborn Tyrant

Trample
Whenever Vaultborn Tyrant or another creature you control with power 4 or greater enters, you gain 3 life and draw a card.
When Vaultborn Tyrant dies, if it's not a token, create a token that's a copy of it, except it's an artifact in addition to its other types.

Magma Sliver

All Slivers have "{T}: Target Sliver creature gets +X/+0 until end of turn, where X is the number of Slivers on the battlefield."

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.

Kiki-Jiki, Mirror Breaker

Haste
{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Vampire Nocturnus

Play with the top card of your library revealed.
As long as the top card of your library is black, Vampire Nocturnus and other Vampire creatures you control get +2/+1 and have flying.

Zombie

Snake

Eldrazi Scion

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Eldrazi Spawn

Dragon

Aura Shards

Whenever a creature you control enters, you may destroy target artifact or enchantment.

Polyraptor

Enrage — Whenever Polyraptor is dealt damage, create a token that's a copy of Polyraptor.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Warleader's Call

Creatures you control get +1/+1.
Whenever a creature you control enters, Warleader's Call deals 1 damage to each opponent.

Ghalta, Stampede Tyrant

Trample
When Ghalta, Stampede Tyrant enters, put any number of creature cards from your hand onto the battlefield.