Trample
This creature enters with four +1/+1 counters on it.
Whenever this creature attacks or blocks, remove a +1/+1 counter from it at end of combat.
: Put a +1/+1 counter on this creature.

When this creature enters, venture into the dungeon. (Enter the first room or advance to the next room.)
As long as you've completed a dungeon, this creature gets +3/+0 and has flying.

Flash
When this creature enters, draw a card, then discard a card.

At the beginning of your upkeep, you may transform this creature.

You may have this creature enter as a copy of any creature on the battlefield.

When Clone Crafter enters, conjure a duplicate of a random creature card from your opponent's library into your hand. It perpetually gains "You may spend mana as though it were mana of any color to cast this spell."

For each creature target player controls, create a token that's a copy of that creature.

Imprint — When this creature enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom of your library in any order.
When this creature dies, turn the exiled card face up. If it's a creature card, put it onto the battlefield under your control.

As an additional cost to cast this spell, choose a creature you control or a warped creature card you own in exile.
Close Encounter deals damage equal to the power of the chosen creature or card to target creature.

Whenever a creature you control becomes blocked, this enchantment deals 1 damage to any target.

This spell costs less to cast during your end step.
Destroy target creature or planeswalker you don't control. Put a +1/+1 counter on up to one target creature you control.

All Slivers have ": Regenerate this permanent."

Whenever another permanent you control becomes the target of a spell or ability an opponent controls, you may return that permanent to its owner's hand.

Flying
First strike

Flying
This creature can block only creatures with flying.

Flying
This creature can block only creatures with flying.

Flying
This creature can block only creatures with flying.

Haste
When Cloud enters, attach up to one target Equipment you control to it.
Whenever Cloud attacks, draw a card for each equipped attacking creature you control. Then if Cloud has power 7 or greater, create two Treasure tokens.

As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost less to cast.

When Cloud enters, search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
As long as Cloud is equipped, if a triggered ability of Cloud or an Equipment attached to it triggers, that ability triggers an additional time.

Flying
Particle Beam — When Cloud of Darkness enters, target creature an opponent controls gets -X/-X until end of turn, where X is the number of permanent cards in your graveyard.

Flying
When this creature enters, untap up to two lands.
Cycling

Flying
This creature can block only creatures with flying.

During your turn, as long as Cloud is equipped, it has double strike and indestructible.
Equip abilities you activate that target Cloud cost less to activate.

Flying
This creature can block only creatures with flying.

Flying
This creature can block only creatures with flying.

Flying
Cloud Sprite can block only creatures with flying.

Flying
When this creature enters, you gain 2 life and draw two cards.