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.

Plains

Wicked Visitor

Whenever an enchantment you control is put into a graveyard from the battlefield, each opponent loses 1 life.

Final Payment

As an additional cost to cast this spell, pay 5 life or sacrifice a creature or enchantment.
Destroy target creature.

Withercrown

Enchant creature
Enchanted creature has base power 0 and has "At the beginning of your upkeep, you lose 1 life unless you sacrifice this creature."

Scrollshift

Exile up to one target artifact, creature, or enchantment you control, then return it to the battlefield under its owner's control.
Draw a card.

Flicker of Fate

Exile target creature or enchantment, then return it to the battlefield under its owner's control.

Cooped Up

Enchant creature
Enchanted creature can't attack or block.
{2}{W}: Exile enchanted creature.

Candletrap

Enchant creature
Enchanted creature has defender.
Prevent all combat damage that would be dealt by enchanted creature.
Coven — {2}{W}, Sacrifice Candletrap: Exile enchanted creature. Activate only if you control three or more creatures with different powers.

Omen of the Dead

Flash
When Omen of the Dead enters, return target creature card from your graveyard to your hand.
{2}{B}, Sacrifice Omen of the Dead: Scry 2.

Slumbering Keepguard

Whenever an enchantment you control enters, scry 1.
{2}{W}: Slumbering Keepguard gets +1/+1 until end of turn for each enchantment you control.

Kor Skyfisher

Flying
When Kor Skyfisher enters, return a permanent you control to its owner's hand.