Betrayer's Bargain

As an additional cost to cast this spell, sacrifice a creature or enchantment or pay {2}.
Betrayer's Bargain deals 5 damage to target creature. If that creature would die this turn, exile it instead.

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Disturbing Mirth

When Disturbing Mirth enters, you may sacrifice another enchantment or creature. If you do, draw two cards.
When you sacrifice Disturbing Mirth, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Spiteful Hexmage

When Spiteful Hexmage enters, create a Cursed Role token attached to target creature you control. (If you control another Role on it, put that one into the graveyard. Enchanted creature is 1/1.)

Final Vengeance

As an additional cost to cast this spell, sacrifice a creature or enchantment.
Exile target creature.

Rottenmouth Viper

As an additional cost to cast this spell, you may sacrifice any number of nonland permanents. This spell costs {1} less to cast for each permanent sacrificed this way.
Whenever Rottenmouth Viper enters or attacks, put a blight counter on it. Then for each blight counter on it, each opponent loses 4 life unless that player sacrifices a nonland permanent or discards a card.

Urabrask's Forge

At the beginning of combat on your turn, put an oil counter on Urabrask's Forge, then create an X/1 red Phyrexian Horror creature token with trample and haste, where X is the number of oil counters on Urabrask's Forge. Sacrifice that token at the beginning of the next end step.

Fear of Missing Out

When Fear of Missing Out enters, discard a card, then draw a card.
Delirium — Whenever Fear of Missing Out attacks for the first time each turn, if there are four or more card types among cards in your graveyard, untap target creature. After this phase, there is an additional combat phase.

Duress

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

Hopeless Nightmare

When Hopeless Nightmare enters, each opponent discards a card and loses 2 life.
When Hopeless Nightmare is put into a graveyard from the battlefield, scry 2.
{2}{B}: Sacrifice Hopeless Nightmare.

Blackcleave Cliffs

Blackcleave Cliffs enters tapped unless you control two or fewer other lands.
{T}: Add {B} or {R}.

Swamp

Mountain

Vengeful Possession

Gain control of target creature until end of turn. Untap it. It gains haste until end of turn. You may discard a card. If you do, draw a card.

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Undead Sprinter

Trample, haste
You may cast Undead Sprinter from your graveyard if a non-Zombie creature died this turn. If you do, Undead Sprinter enters with a +1/+1 counter on it.