Flash

When Ashiok's Erasure enters the battlefield, exile target spell.

Your opponents can't cast spells with the same name as the exiled card.

When Ashiok's Erasure leaves the battlefield, return the exiled card to its owner's hand.

{3}{U}: Ashiok's Skulker can't be blocked this turn.

Spells and abilities your opponents control can't cause their controller to search their library.

-1: Target player mills four cards. Then exile each opponent's graveyard.

+1: Create a 2/3 blue and black Nightmare creature token with "Whenever this creature attacks or blocks, each opponent exiles the top two cards of their library."

-3: Return target nonland permanent to its owner's hand, then that player exiles a card from their hand.

-7: You may cast up to three spells from among face-up cards your opponents own from exile without paying their mana costs.

+2: Exile the top three cards of target opponent's library.

-X: Put a creature card with mana value X exiled with Ashiok, Nightmare Weaver onto the battlefield under your control. That creature is a Nightmare in addition to its other types.

-10: Exile all cards from all opponents' hands and graveyards.

+2: Draw a card. Each player mills two cards.

-5: Put target creature card from a graveyard onto the battlefield under your control.

-11: Gain control of all creatures target opponent controls.

Devoid (This card has no color.)

Flying

When Inverter of Truth enters the battlefield, exile all cards from your library face down, then shuffle all cards from your graveyard into your library.

If you would draw a card while your library has no cards in it, you win the game instead.

+1: Target player mills two cards. Draw a card.

-8: Draw seven cards. Then if your library has no cards in it, you win the game.

+2: Look at the top card of target player's library. You may put that card on the bottom of that player's library.

0: Draw three cards, then put two cards from your hand on top of your library in any order.

-1: Return target creature to its owner's hand.

-12: Exile all cards from target player's library, then that player shuffles their hand into their library.

+4: Target player exiles a card from their hand.

-3: Exile target permanent.

-14: Restart the game, leaving in exile all non-Aura permanent cards exiled with Karn Liberated. Then put those cards onto the battlefield under your control.

+1: Reveal the top two cards of your library. An opponent chooses one of them. Put that card into your hand and exile the other with a silver counter on it.

-1: Put a card you own with a silver counter on it from exile into your hand.

-2: Create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."

Activated abilities of artifacts your opponents control can't be activated.

+1: Until your next turn, up to one target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value.

-2: You may reveal an artifact card you own from outside the game or choose a face-up artifact card you own in exile. Put that card into your hand.

When you cast this spell, draw four cards.

Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents.)

When Kozilek, Butcher of Truth is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

When you cast this spell, if you have fewer than seven cards in hand, draw cards equal to the difference.

Menace

Discard a card with mana value X: Counter target spell with mana value X.

Hexproof

Whenever a creature card is put into an opponent's graveyard from anywhere, you may have Lazav, Dimir Mastermind become a copy of that card, except its name is Lazav, Dimir Mastermind, it's legendary in addition to its other types, and it has hexproof and this ability.

Swimmer in Nightmares gets +3/+0 as long as there are ten or more cards in a single graveyard.

Swimmer in Nightmares can't be blocked as long as you control an Ashiok planeswalker.

+1: Tap target permanent. It doesn't untap during its controller's next untap step.

-2: Draw a card for each tapped creature target player controls.

-8: You get an emblem with "You have no maximum hand size" and "Whenever a card is put into your graveyard from anywhere, you may return it to your hand."

When you cast this spell, exile two target permanents.

Indestructible

Whenever Ulamog, the Ceaseless Hunger attacks, defending player exiles the top twenty cards of their library.

When you cast this spell, destroy target permanent.

Indestructible

Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents.)

When Ulamog, the Infinite Gyre is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.