As The Mimeoplasm enters, you may exile two creature cards from graveyards. If you do, it enters as a copy of one of those cards with a number of additional +1/+1 counters on it equal to the power of the other card.

As this creature enters, choose a color.
All Slivers have protection from the chosen color.

Indestructible
As this creature enters, choose a player.
Whenever this creature is dealt damage, it deals that much damage to the chosen player.
: This creature deals 1 damage to itself.

This artifact enters tapped.
, , Sacrifice this artifact: Target player loses the game.

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

Rather than pay for each previous time you've cast this spell from the command zone this game, pay 2 life that many times.
Flying, lifelink
Whenever a player casts a spell, they lose 2 life.

Prevent all combat damage that would be dealt to you this turn. For each 1 damage prevented this way, create a 2/1 white and black Inkling creature token with flying.

Whenever a Sliver deals combat damage to a player, its controller may create a 1/1 colorless Sliver creature token.

Whenever a creature you control dies, you gain 1 life and draw a card.

When this creature enters, double the number of each kind of counter on any number of target permanents.

Whenever a creature attacks you or a planeswalker you control, each Dragon you control deals 1 damage to that creature.
+1: Until end of turn, each planeswalker you control becomes a 4/4 red Dragon creature and gains flying.
−3: Create a 4/4 red Dragon creature token with flying.

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Partner with Okaun, Eye of Chaos (When this creature enters, target player may put Okaun into their hand from their library, then shuffle.)
At the beginning of combat on your turn, flip a coin until you lose a flip.
Whenever a player wins a coin flip, draw a card.

, : Gain control of target legendary permanent. (This effect lasts indefinitely.)

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever this creature deals combat damage to a player, that player skips their next combat phase.

Tap an untapped Wizard you control: Draw a card.

Reach
Whenever this creature or another Cat you control enters, you may destroy target artifact or enchantment.

Search target opponent's library for a creature card and put that card onto the battlefield under your control. Then that player shuffles.

After the second main phase this turn, there's an additional combat phase followed by an additional main phase. At the beginning of that combat, untap all creatures that attacked this turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Exile the top five cards of your library. You may play cards exiled this way until the end of your next turn.
You may play an additional land this turn.

All Sliver creatures have ": This creature deals 2 damage to any target and 3 damage to itself."

Menace
When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Destroy all artifacts and enchantments. You gain 2 life for each permanent destroyed this way.

Flying
: Search your library for a Dragon permanent card and put it into your graveyard. If you do, Scion of the Ur-Dragon becomes a copy of that card until end of turn. Then shuffle.

Lifelink
When this creature enters, search your library for a card, put it into your graveyard, then shuffle.
Spells you cast from your graveyard cost less to cast.

When this enchantment enters, you draw four cards and you lose 4 life.
At the beginning of your upkeep, if you control four or more Demons with different names, you win the game.

Vigilance, trample
, : Exile another target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Whenever you tap a Forest for mana, add an additional .
+1: Put three +1/+1 counters on up to one target noncreature land you control. Untap it. It becomes a 0/0 Elemental creature with vigilance and haste that's still a land.
−8: You get an emblem with "Lands you control have indestructible." Search your library for any number of Forest cards, put them onto the battlefield tapped, then shuffle.

At the beginning of your upkeep, if you have 200 or more cards in your library, you win the game.

When this creature enters, you may search your library for a creature card, put that card into your graveyard, then shuffle.
Unearth (: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Devour 2 (As this creature enters, you may sacrifice any number of creatures. It enters with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on this creature.

Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with this enchantment on the bottom of their library in a random order.

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Play with the top card of your library revealed.
You may play lands and cast spells from the top of your library.

Add for each tapped land your opponents control.