Overseer of the Damned

Flying
When Overseer of the Damned enters, you may destroy target creature.
Whenever a nontoken creature an opponent controls dies, create a tapped 2/2 black Zombie creature token.

World-Weary

Enchant creature
Enchanted creature gets -4/-4.
Basic landcycling {1}{B} ({1}{B}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Swamp

Bone Shredder

Flying
Echo {2}{B} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Bone Shredder enters, destroy target nonartifact, nonblack creature.

Annihilate

Destroy target nonblack creature. It can't be regenerated.
Draw a card.

Diregraf Horde

When Diregraf Horde enters, create two 2/2 black Zombie creature tokens with decayed. When you do, exile up to two target cards from graveyards. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Crushing Disappointment

Each player loses 2 life. You draw two cards.

Harvest Fear

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

Reaper of Night

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

Reaper of Night // Harvest Fear

Tizerus Charger

Escape—{4}{B}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Tizerus Charger escapes with your choice of a +1/+1 counter or a flying counter on it.

Umbral Juke

Choose one —
• Target player sacrifices a creature or planeswalker of their choice.
• Create a 2/1 white and black Inkling creature token with flying.

Pharika's Spawn

Escape—{5}{B}, Exile three other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Pharika's Spawn escapes with two +1/+1 counters on it. When it enters this way, each opponent sacrifices a non-Gorgon creature of their choice.

Tendrils of Corruption

Tendrils of Corruption deals X damage to target creature and you gain X life, where X is the number of Swamps you control.

Tragic Fall

Target creature gets -3/-3 until end of turn.
Hellbent — That creature gets -13/-13 until end of turn instead if you have no cards in hand.

Murder

Spell Satchel

Magecraft — Whenever you cast or copy an instant or sorcery spell, put a book counter on Spell Satchel.
{T}, Remove a book counter from Spell Satchel: Add {C}.
{3}, {T}, Remove three book counters from Spell Satchel: Draw a card.