Swamp

Go for the Throat

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Vampiric Rites

{1}{B}, Sacrifice a creature: You gain 1 life and draw a card.

Demon's Disciple

When Demon's Disciple enters, each player sacrifices a creature or planeswalker.

Archfiend's Vessel

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
When Archfiend's Vessel enters, if it entered from your graveyard or you cast it from your graveyard, exile it. If you do, create a 5/5 black Demon creature token with flying.

Blood Celebrant

{B}, Pay 1 life: Add one mana of any color.

Taborax, Hope's Demise

Flying
Taborax, Hope's Demise has lifelink as long as it has five or more +1/+1 counters on it.
Whenever another nontoken creature you control dies, put a +1/+1 counter on Taborax. If that creature was a Cleric, you may draw a card. If you do, you lose 1 life.

Disciple of the Vault

Whenever an artifact is put into a graveyard from the battlefield, you may have target opponent lose 1 life.

Dark Supplicant

{T}, Sacrifice three Clerics: Search your graveyard, hand, and/or library for a card named Scion of Darkness and put it onto the battlefield. If you search your library this way, shuffle.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Scion of Darkness

Trample
Whenever Scion of Darkness deals combat damage to a player, you may put target creature card from that player's graveyard onto the battlefield under your control.
Cycling {3} ({3}, Discard this card: Draw a card.)

Priest of the Blood Rite

When Priest of the Blood Rite enters, create a 5/5 black Demon creature token with flying.
At the beginning of your upkeep, you lose 2 life.

Disciple of Malice

Protection from white
Cycling {2} ({2}, Discard this card: Draw a card.)

Skirsdag High Priest

Morbid — {T}, Tap two untapped creatures you control: Create a 5/5 black Demon creature token with flying. Activate only if a creature died this turn.

Thriving Moor

Thriving Moor enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Rite of Belzenlok

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Create two 0/1 black Cleric creature tokens.
III — Create a 6/6 black Demon creature token with flying, trample, and "At the beginning of your upkeep, sacrifice another creature. If you can't, this creature deals 6 damage to you."

Ormendahl, the Corrupter

Flying, trample, lifelink
Sacrifice another creature: Draw a card.

Jerren, Corrupted Bishop

Whenever Jerren, Corrupted Bishop enters or another nontoken Human you control dies, you lose 1 life and create a 1/1 white Human creature token.
{2}: Target Human you control gains lifelink until end of turn.
At the beginning of your end step, if you have exactly 13 life, you may pay {4}{B}{B}. If you do, transform Jerren.

Jerren, Corrupted Bishop // Ormendahl, the Corrupter

Nullpriest of Oblivion

Kicker {3}{B}
Menace, lifelink
When Nullpriest of Oblivion enters, if it was kicked, return target creature card from your graveyard to the battlefield.