Getting

Silent Specter

Flying
Whenever this creature 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.)

Shimian Specter

Flying
Whenever this creature deals combat damage to a player, that player reveals their hand. You choose a nonland card from it. Search that player's graveyard, hand, and library for all cards with the same name as that card and exile them. Then that player shuffles.

Have

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Don't Have

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Harvest Fear

Target opponent discards two cards. (Then exile this card. You may cast the creature later from exile.)

Reaper of Night

Whenever this creature attacks, if defending player has two or fewer cards in hand, it gains flying until end of turn.

Reaper of Night // Harvest Fear

Have but different Printing

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Trazyn the Infinite

Deathtouch
Prismatic Gallery — As long as Trazyn is on the battlefield, it has all activated abilities of all artifact cards in your graveyard.

Morph

(You can cover a face-down creature with this reminder card.
A card with morph can be turned face up any time for its morph cost.)

Herald of Anguish

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Flying
At the beginning of your end step, each opponent discards a card.
{1}{B}, Sacrifice an artifact: Target creature gets -2/-2 until end of turn.

Necrogoyf

Necrogoyf's power is equal to the number of creature cards in all graveyards.
At the beginning of each player's upkeep, that player discards a card.
Madness {1}{B}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Fell Specter

Flying
When this creature enters, target opponent discards a card.
Whenever an opponent discards a card, that player loses 2 life.

Whispering Specter

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this creature deals combat damage to a player, you may sacrifice it. If you do, that player discards a card for each poison counter they have.

Guul Draz Specter

Flying
This creature gets +3/+3 as long as an opponent has no cards in hand.
Whenever this creature deals combat damage to a player, that player discards a card.

Shrieking Affliction

At the beginning of each opponent's upkeep, if that player has one or fewer cards in hand, they lose 3 life.

Urgoros, the Empty One

Flying
Whenever Urgoros deals combat damage to a player, that player discards a card at random. If the player can't, you draw a card.

Swamp

Archon of Cruelty

Flying
Whenever this creature enters or attacks, target opponent sacrifices a creature or planeswalker of their choice, discards a card, and loses 3 life. You draw a card and gain 3 life.

Megrim

Whenever an opponent discards a card, this enchantment deals 2 damage to that player.

Hollow Marauder

This spell costs {1} less to cast for each creature card in your graveyard.
Flying
When this creature enters, any number of target opponents each discard a card. For each of those opponents who didn't discard a card with mana value 4 or greater, draw a card.

Liliana's Specter

Flying
When this creature enters, each opponent discards a card.

On an Adventure

After an Adventure resolves, you can place the exiled card here. You may cast the creature from exile.

Order of Yawgmoth

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever this creature deals damage to a player, that player discards a card.

Specter of the Fens

Flying
{5}{B}: Target opponent loses 2 life and you gain 2 life.

Headless Specter

Flying
Hellbent — Whenever this creature deals combat damage to a player, if you have no cards in hand, that player discards a card at random.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Raiders' Wake

Whenever an opponent discards a card, that player loses 2 life.
Raid — At the beginning of your end step, if you attacked this turn, target opponent discards a card.

Sangromancer

Flying
Whenever a creature an opponent controls dies, you may gain 3 life.
Whenever an opponent discards a card, you may gain 3 life.

Withering Torment

Destroy target creature or enchantment. You lose 2 life.

Hollow Specter

Flying
Whenever this creature 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.

The Haunt of Hightower

Flying, lifelink
Whenever The Haunt of Hightower attacks, defending player discards a card.
Whenever a card is put into an opponent's graveyard from anywhere, put a +1/+1 counter on The Haunt of Hightower.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Junji, the Midnight Sky

Flying, menace
When Junji dies, choose one —
• Each opponent discards two cards and loses 2 life.
• Put target non-Dragon creature card from a graveyard onto the battlefield under your control. You lose 2 life.

Davriel, Rogue Shadowmage

At the beginning of each opponent's upkeep, if that player has one or fewer cards in hand, Davriel deals 2 damage to them.
−1: Target player discards a card.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Shrieking Specter

Flying
Whenever this creature attacks, defending player discards a card.

Bontu's Monument

Black creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

Needle Specter

Flying
Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever this creature deals combat damage to a player, that player discards that many cards.

Changeling Outcast

Changeling (This card is every creature type.)
This creature can't block and can't be blocked.

Entropic Specter

Flying
As this creature 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 this creature deals damage to a player, that player discards a card.

Hypnotic Specter

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

Scythe Specter

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

Abyssal Specter

Flying
Whenever this creature deals damage to a player, that player discards a card.

Specter of Mortality

Flying
When this creature enters, you may exile one or more creature cards from your graveyard. When you do, each other creature gets -X/-X until end of turn, where X is the number of cards exiled this way.