Boarded Window

Creatures attacking you get -1/-0.
At the beginning of each end step, if you were dealt 4 or more damage this turn, exile Boarded Window.

The Flesh Is Weak

When The Flesh Is Weak enters, put a +1/+1 counter on each creature you control.
Creatures you control with +1/+1 counters on them are artifacts in addition to their other types.
Nonartifact creatures get -1/-1.

Azorius Skyguard

Flying, first strike
Creatures your opponents control get -1/-0.

Night of Souls' Betrayal

Grim Hireling

Whenever one or more creatures you control deal combat damage to a player, create two Treasure tokens.
{B}, Sacrifice X Treasures: Target creature gets -X/-X until end of turn. Activate only as a sorcery.

Ethereal Absolution

Creatures you control get +1/+1.
Creatures your opponents control get -1/-1.
{2}{W}{B}: Exile target card from an opponent's graveyard. If it was a creature card, you create a 1/1 white and black Spirit creature token with flying.

Waker of Waves

Creatures your opponents control get -1/-0.
{1}{U}, Discard Waker of Waves: Look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.

Kaervek, the Spiteful

Sludge Monster

Whenever Sludge Monster enters or attacks, put a slime counter on up to one other target creature.
Non-Horror creatures with slime counters on them lose all abilities and have base power and toughness 2/2.

Haunter of Nightveil

Creatures your opponents control get -1/-0.

Cumber Stone

Dampening Pulse

Shipwreck Singer

Flying
{1}{U}: Target creature an opponent controls attacks this turn if able.
{1}{B}, {T}: Attacking creatures get -1/-1 until end of turn.