Flying, soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Breathkeeper Seraph is paired with another creature, each of those creatures has "When this creature dies, you may return it to the battlefield under its owner's control at the beginning of your next upkeep."

Flying, trample
When Demonlord Belzenlok enters, exile cards from the top of your library until you exile a nonland card, then put that card into your hand. If the card's mana value is 4 or greater, repeat this process. Demonlord Belzenlok deals 1 damage to you for each card put into your hand this way.

At the beginning of each end step, each player discards their hand.

This spell can't be countered.
Trample, hexproof

First strike, hexproof
Whenever Narset attacks, exile the top four cards of your library. Until end of turn, you may cast noncreature spells from among those cards without paying their mana costs.

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a Human deals damage to you, destroy it.
Other non-Human creatures you control get +1/+1 and have undying. (When a creature with undying 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.)

Deathtouch
Whenever this creature enters or attacks, create two 2/2 black Zombie creature tokens.

Your opponents and permanents your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.
−3: Exile target creature.

At the beginning of your upkeep, choose target opponent. Until end of turn, that player can't cast spells, you may look at the top card of their library any time, you may play the top card of their library, and you may spend mana as though it were mana of any color to cast spells this way.

Other Snake creatures you control get +2/+2.
Whenever a Snake you control deals combat damage to a player, you may draw a card.

Flying, haste
Other creatures you control have haste.
Whenever an opponent casts a creature or planeswalker spell with the same name as a card in their graveyard, that player loses 10 life.

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Flying
Landfall — Whenever a land you control enters, you may exile target nonland permanent other than this creature.
When this creature leaves the battlefield, return all cards exiled with it to the battlefield under their owners' control.

You gain X life and draw X cards, where X is the number of creatures you control. Creatures you control get +1/+1 until end of turn.

Each player shuffles their hand and graveyard into their library, then draws seven cards.
Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Deathtouch, lifelink
When this creature dies, create a 3/3 colorless Phyrexian Wurm artifact creature token with deathtouch and a 3/3 colorless Phyrexian Wurm artifact creature token with lifelink.

This creature enters with three +1/+1 counters on it.
Remove a +1/+1 counter from this creature: It deals 1 damage to any target.

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Deadeye Navigator is paired with another creature, each of those creatures has ": Exile this creature, then return it to the battlefield under your control."

Flying, deathtouch
When Dragonlord Silumgar enters, gain control of target creature or planeswalker for as long as you control Dragonlord Silumgar.

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.

During your turn, each creature assigns combat damage equal to its toughness rather than its power.
Whenever Baldin attacks, up to one hundred target creatures each get +0/+X until end of turn, where X is the number of cards in your hand.

Vigilance
Hydra spells you cast cost less to cast.
Whenever a creature you control becomes the target of a spell, Gargos fights up to one target creature you don't control.

, : Search your library for a permanent card, put it onto the battlefield, then shuffle.

Flying
Landfall — Whenever a land you control enters, you may gain control of target creature for as long as you control this creature.

Flying
Whenever a permanent owned by another player is put into a graveyard from the battlefield, you draw a card and you lose 1 life.

Vigilance
Whenever this creature enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

+1: Chandra deals 3 damage to each opponent.
−2: You may cast target red instant or sorcery card from your graveyard. If that spell would be put into your graveyard, exile it instead.
−8: Discard your hand, then draw seven cards. Until end of turn, you may cast spells from your hand without paying their mana costs.

When this artifact enters, put a -1/-1 counter on each creature target player controls.
, : Proliferate twice. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Flying
Whenever you draw a card, create a 1/1 blue and red Insect creature token with flying and haste.
: Draw a card, then discard a card.
When The Locust God dies, return it to its owner's hand at the beginning of the next end step.

Creature and planeswalker spells you cast have affinity for artifacts. (They cost less to cast for each artifact you control.)
+2: Tezzeret 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.

Whenever a player casts an instant or sorcery spell, each other player copies that spell. Each of those players may choose new targets for their copy.

When Kogla enters, it fights up to one target creature you don't control.
Whenever Kogla attacks, destroy target artifact or enchantment defending player controls.
: Return target Human you control to its owner's hand. Kogla gains indestructible until end of turn.

Reach (This creature can block creatures with flying.)
You may play lands from your graveyard.
If a land entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

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.
, Sacrifice ten nonland permanents: Each opponent loses 10 life.