Urborg Mindsucker

{B}, Sacrifice Urborg Mindsucker: Target opponent discards a card at random. Activate only as a sorcery.

Fear of Abduction

As an additional cost to cast this spell, exile a creature you control.
Flying
When Fear of Abduction enters, exile target creature an opponent controls.
When Fear of Abduction leaves the battlefield, put each card exiled with it into its owner's hand.

Grim Strider

Grim Strider gets -1/-1 for each card in your hand.

Silent Specter

Flying
Whenever Silent Specter deals combat damage to a player, that player discards two cards.
Morph {3}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Will-o'-the-Wisp

Flying (This creature can't be blocked except by creatures with flying or reach.)
{B}: Regenerate Will-o'-the-Wisp. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

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.)

Mesmeric Fiend

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

Mage Hunter

Whenever an opponent casts or copies an instant or sorcery spell, they lose 1 life.

Vebulid

Vebulid enters with a +1/+1 counter on it.
At the beginning of your upkeep, you may put a +1/+1 counter on Vebulid.
When Vebulid attacks or blocks, destroy it at end of combat.

Doomsday Specter

Flying
When Doomsday Specter enters, return a blue or black creature you control to its owner's hand.
Whenever Doomsday Specter deals combat damage to a player, look at that player's hand and choose a card from it. The player discards that card.

Cosmic Horror

First strike
At the beginning of your upkeep, destroy Cosmic Horror unless you pay {3}{B}{B}{B}. If Cosmic Horror is destroyed this way, it deals 7 damage to you.

Yarok's Fenlurker

When Yarok's Fenlurker enters, each opponent exiles a card from their hand.
{2}{B}: Yarok's Fenlurker gets +1/+1 until end of turn.

Blazing Specter

Flying, haste
Whenever Blazing Specter deals combat damage to a player, that player discards a card.

Phyrexian Obliterator

Trample
Whenever a source deals damage to Phyrexian Obliterator, that source's controller sacrifices that many permanents of their choice.

Hollow Specter

Flying
Whenever Hollow Specter deals combat damage to a player, you may pay {X}. If you do, that player reveals X cards from their hand and you choose one of them. That player discards that card.

Phyrexian Vatmother

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
At the beginning of your upkeep, you get a poison counter.

Plague Mare

Plague Mare can't be blocked by white creatures.
When Plague Mare enters, creatures your opponents control get -1/-1 until end of turn.

Scythe Specter

Flying
Whenever Scythe Specter deals combat damage to a player, each opponent discards a card. Each player who discarded a card with the highest mana value among cards discarded this way loses life equal to that mana value.

Frightcrawler

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Threshold — As long as seven or more cards are in your graveyard, Frightcrawler gets +2/+2 and can't block.

Witch Engine

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{T}: Add {B}{B}{B}{B}. Target opponent gains control of Witch Engine. (Activate only as an instant.)

Specter's Shroud

Equipped creature gets +1/+0.
Whenever equipped creature deals combat damage to a player, that player discards a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Childhood Horror

Flying
Threshold — As long as seven or more cards are in your graveyard, Childhood Horror gets +2/+2 and can't block.

Banehound

Krovikan Horror

At the beginning of the end step, if Krovikan Horror is in your graveyard with a creature card directly above it, you may return Krovikan Horror to your hand.
{1}, Sacrifice a creature: Krovikan Horror deals 1 damage to any target.

Rusted Slasher

Sacrifice an artifact: Regenerate Rusted Slasher.

Phyrexian Negator

Trample
Whenever Phyrexian Negator is dealt damage, sacrifice that many permanents.

Tsabo Tavoc

First strike, protection from legendary creatures
{B}{B}, {T}: Destroy target legendary creature. It can't be regenerated.

getting more of

Nightmare

Flying (This creature can't be blocked except by creatures with flying or reach.)
Nightmare's power and toughness are each equal to the number of Swamps you control.

Urborg Stalker

At the beginning of each player's upkeep, if that player controls a nonblack, nonland permanent, Urborg Stalker deals 1 damage to that player.

Abomination

Whenever Abomination blocks or becomes blocked by a green or white creature, destroy that creature at end of combat.

Shimian Night Stalker

{B}, {T}: All damage that would be dealt to you this turn by target attacking creature is dealt to Shimian Night Stalker instead.

Hypnotic Specter

Flying
Whenever Hypnotic Specter deals damage to an opponent, that player discards a card at random.

Entropic Specter

Flying
As Entropic Specter enters, choose an opponent.
Entropic Specter's power and toughness are each equal to the number of cards in the chosen player's hand.
Whenever Entropic Specter deals damage to a player, that player discards a card.

Boneshard Slasher

Flying
Threshold — As long as seven or more cards are in your graveyard, Boneshard Slasher gets +2/+2 and has "When Boneshard Slasher becomes the target of a spell or ability, sacrifice it."

Scrounger of Souls

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Eater of the Dead

{0}: If Eater of the Dead is tapped, exile target creature card from a graveyard and untap Eater of the Dead.

Squirming Mass

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Delraich

You may sacrifice three black creatures rather than pay this spell's mana cost.
Trample

Devouring Strossus

Flying, trample
At the beginning of your upkeep, sacrifice a creature.
Sacrifice a creature: Regenerate Devouring Strossus.

Underworld Charger

Underworld Charger can't block.
Escape—{4}{B}, Exile three other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Underworld Charger escapes with two +1/+1 counters on it.

Gravegouger

When Gravegouger enters, exile up to two target cards from a single graveyard.
When Gravegouger leaves the battlefield, return the exiled cards to their owner's graveyard.