Gurmag Angler

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

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Mephitic Vapors

All creatures get -1/-1 until end of turn.
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.)

Stinkweed Imp

Flying
Whenever Stinkweed Imp deals combat damage to a creature, destroy that creature.
Dredge 5 (If you would draw a card, you may mill five cards instead. If you do, return this card from your graveyard to your hand.)

Songs of the Damned

Add {B} for each creature card in your graveyard.

Golgari Brownscale

When Golgari Brownscale is put into your hand from your graveyard, you gain 2 life.
Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)

Serene Heart

Caustic Caterpillar

{1}{G}, Sacrifice Caustic Caterpillar: Destroy target artifact or enchantment.

Commune with the Gods

Reveal the top five cards of your library. You may put a creature or enchantment card from among them into your hand. Put the rest into your graveyard.

Drown in Filth

Choose target creature. Mill four cards, then that creature gets -1/-1 until end of turn for each land card in your graveyard.

Nimble Mongoose

Shroud (This creature can't be the target of spells or abilities.)
Threshold — Nimble Mongoose gets +2/+2 as long as seven or more cards are in your graveyard.

Grave Scrabbler

Madness {1}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
When Grave Scrabbler enters, if its madness cost was paid, you may return target creature card from a graveyard to its owner's hand.

Gnaw to the Bone

You gain 2 life for each creature card in your graveyard.
Flashback {2}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Bojuka Bog

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

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Forest

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Swamp

Chainer's Edict

Target player sacrifices a creature of their choice.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ghastly Demise

Destroy target nonblack creature if its toughness is less than or equal to the number of cards in your graveyard.