Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Draugr Necromancer

If a nontoken creature an opponent controls would die, exile that card with an ice counter on it instead.
You may cast spells from among cards in exile your opponents own with ice counters on them, and you may spend mana from snow sources as though it were mana of any color to cast those spells.

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Shriekmaw enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker of their choice.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Soul Shatter

Each opponent sacrifices a creature or planeswalker with the highest mana value among creatures and planeswalkers they control.

Price of Fame

This spell costs {2} less to cast if it targets a legendary creature.
Destroy target creature.
Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Bone Shards

As an additional cost to cast this spell, sacrifice a creature or discard a card.
Destroy target creature or planeswalker.

Damnation

Destroy all creatures. They can't be regenerated.

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Dead of Winter

All nonsnow creatures get -X/-X until end of turn, where X is the number of snow permanents you control.

Avatar of Woe

If there are ten or more creature cards total in all graveyards, this spell costs {6} less to cast.
Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
{T}: Destroy target creature. It can't be regenerated.

Baleful Mastery

You may pay {1}{B} rather than pay this spell's mana cost.
If the {1}{B} cost was paid, an opponent draws a card.
Exile target creature or planeswalker.

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Murderous Cut

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Destroy target creature.

Go for the Throat

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Hagra Broodpit

Hagra Broodpit enters tapped.
{T}: Add {B}.

Hagra Mauling

This spell costs {1} less to cast if an opponent controls no basic lands.
Destroy target creature.

Hagra Mauling // Hagra Broodpit

Victimize

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

Plaguecrafter

When Plaguecrafter enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Feed the Swarm

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

Curtains' Call

Undaunted (This spell costs {1} less to cast for each opponent.)
Destroy two target creatures.

Sol Ring

Heartless Act

Choose one —
• Destroy target creature with no counters on it.
• Remove up to three counters from target creature.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Gisa, Glorious Resurrector

If a creature an opponent controls would die, exile it instead.
At the beginning of your upkeep, put all creature cards exiled with Gisa, Glorious Resurrector onto the battlefield under your control. They gain decayed. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Snow-Covered Swamp

Cavalier of Night

Lifelink
When Cavalier of Night enters, you may sacrifice another creature. When you do, destroy target creature an opponent controls.
When Cavalier of Night dies, return target creature card with mana value 3 or less from your graveyard to the battlefield.

Infernal Grasp

Destroy target creature. You lose 2 life.

Blood on the Snow

Choose one —
• Destroy all creatures.
• Destroy all planeswalkers.
Then return a creature or planeswalker card with mana value X or less from your graveyard to the battlefield, where X is the amount of {S} spent to cast this spell. ({S} is mana from a snow source.)

Noxious Gearhulk

Menace
When Noxious Gearhulk enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.