Have

Megrim

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

Swamp

Shrieking Affliction

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

Raven's Crime

Target player discards a card.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Hypnotic Specter

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

Dark Ritual

Island

Wrench Mind

Target player discards two cards unless they discard an artifact card.

Hymn to Tourach

Target player discards two cards at random.

Wistful Thinking

Target player draws two cards, then discards four cards.

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.

Duress

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

Recoil

Return target permanent to its owner's hand. Then that player discards a card.

Nyxathid

As Nyxathid enters, choose an opponent.
Nyxathid gets -1/-1 for each card in the chosen player's hand.