Megrim

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

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.)

Ice Floe

You may choose not to untap Ice Floe during your untap step.
{T}: Tap target creature without flying that's attacking you. It doesn't untap during its controller's untap step for as long as Ice Floe remains tapped.

Painful Memories

Look at target opponent's hand and choose a card from it. Put that card on top of that player's library.

Blackmail

Target player reveals three cards from their hand and you choose one of them. That player discards that card.

Uncle Istvan

Prevent all damage that would be dealt to Uncle Istvan by creatures.

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

Royal Assassin

Skittering Skirge

Flying
When you cast a creature spell, sacrifice Skittering Skirge.

Persecute

Choose a color. Target player reveals their hand and discards all cards of that color.

Ostracize

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

Dark Ritual

Hypnotic Specter

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

Hymn to Tourach

Target player discards two cards at random.

Swamp

The Rack

As The Rack enters, choose an opponent.
At the beginning of the chosen player's upkeep, The Rack deals X damage to that player, where X is 3 minus the number of cards in their hand.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Ravenous Rats

When Ravenous Rats enters, target opponent discards a card.

Sengir Vampire

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever a creature dealt damage by Sengir Vampire this turn dies, put a +1/+1 counter on Sengir Vampire.