Seymour Flux

At the beginning of your upkeep, you may pay 1 life. If you do, draw a card and put a +1/+1 counter on Seymour Flux.

Susurian Dirgecraft

When this Spacecraft enters, each opponent sacrifices a nontoken creature of their choice.
Station (Tap another creature you control: Put charge counters equal to its power on this Spacecraft. Station only as a sorcery. It's an artifact creature at 7+.)
7+ | Flying

Fleshbag Marauder

When this creature enters, each player sacrifices a creature of their choice.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Feed the Swarm

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

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Dark Ritual

Overkill

Target creature gets -0/-9999 until end of turn.

The Soul Stone

Indestructible
{T}: Add {B}.
{6}{B}, {T}, Exile a creature you control: Harness The Soul Stone. (Once harnessed, its ∞ ability is active.)
∞ — At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.

Susur Secundi, Void Altar

This land enters tapped.
{T}: Add {B}.
Station (Tap another creature you control: Put charge counters equal to its power on this Planet. Station only as a sorcery.)
12+ | {1}{B}, {T}, Pay 2 life, Sacrifice a creature: Draw cards equal to the sacrificed creature's power. Activate only as a sorcery.

Fandaniel, Telophoroi Ascian

Whenever you cast an instant or sorcery spell, surveil 1.
At the beginning of your end step, each opponent may sacrifice a nontoken creature of their choice. Each opponent who doesn't loses 2 life for each instant and sorcery card in your graveyard.

Sephiroth's Intervention

Destroy target creature. You gain 2 life.

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Zero Point Ballad

Destroy all creatures with toughness X or less. You lose X life. If X is 6 or more, return a creature card put into a graveyard this way to the battlefield under your control.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Transpose

Draw a card, then discard a card. You lose 1 life. If this spell was cast from your hand, create a 0/1 black Wizard creature token with "Whenever you cast a noncreature spell, this token deals 1 damage to each opponent."
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.