Annul

Counter target artifact or enchantment spell.

Cast Down

Entropic Decay

Mill four cards. (Then exile this card. You may cast the creature later from exile.)

Gray Slaad

As long as there are four or more creature cards in your graveyard, this creature has menace and deathtouch.

Gray Slaad // Entropic Decay

Dauthi Horror

Shadow (This creature can block or be blocked by only creatures with shadow.)
This creature can't be blocked by white creatures.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Plague Stinger

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Island

Fetid Horror

{B}: This creature gets +1/+1 until end of turn.

Fume Spitter

Sacrifice this creature: Put a -1/-1 counter on target creature.

Thought Scour

Target player mills two cards.
Draw a card.

Infectious Horror

Whenever this creature attacks, each opponent loses 2 life.

Extract a Confession

As an additional cost to cast this spell, you may collect evidence 6. (Exile cards with total mana value 6 or greater from your graveyard.)
Each opponent sacrifices a creature of their choice. If evidence was collected, instead each opponent sacrifices a creature with the greatest power among creatures they control.

Dross Hopper

Sacrifice a creature: This creature gains flying until end of turn.

Mesmeric Fiend

When this creature enters, target opponent reveals their hand and you choose a nonland card from it. Exile that card.
When this creature leaves the battlefield, return the exiled card to its owner's hand.