Maybe

Golgari Guildgate

Golgari Guildgate enters the battlefield tapped.
{T}: Add {B} or {G}.

Doom Blade

Life from the Loam

Return up to three target land cards from your graveyard to your hand.
Dredge 3 (If you would draw a card, you may mill three cards instead. If you do, return this card from your graveyard to your hand.)

Good - strat

Krav, the Unredeemed

Partner with Regna, the Redeemer (When this creature enters the battlefield, target player may put Regna into their hand from their library, then shuffle.)
{B}, Sacrifice X creatures: Target player draws X cards and gains X life. Put X +1/+1 counters on Krav, the Unredeemed.

Plague Wind

Destroy all creatures you don't control. They can't be regenerated.

Harvester of Souls

Deathtouch
Whenever another nontoken creature dies, you may draw a card.

Poison-Tip Archer

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another creature dies, each opponent loses 1 life.

worse version

Midnight Reaper

Whenever a nontoken creature you control dies, Midnight Reaper deals 1 damage to you and you draw a card.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Avenger of Zendikar

When Avenger of Zendikar enters the battlefield, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land enters the battlefield under your control, you may put a +1/+1 counter on each Plant creature you control.

Fine - strat

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.

Have

Zulaport Cutthroat

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Good but $$$

Cabal Coffers

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

good - no strat

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

Greenwarden of Murasa

When Greenwarden of Murasa enters the battlefield, you may return target card from your graveyard to your hand.
When Greenwarden of Murasa dies, you may exile it. If you do, return target card from your graveyard to your hand.

Not good enough

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Castle Locthwain

Castle Locthwain enters the battlefield tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Finality

You may put two +1/+1 counters on a creature you control. Then all creatures get -4/-4 until end of turn.

Find

Return up to two target creature cards from your graveyard to your hand.

Find // Finality

Demonic Tutor

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

Whisper, Blood Liturgist

{T}, Sacrifice two creatures: Return target creature card from your graveyard to the battlefield.

Rune-Scarred Demon

Flying
When Rune-Scarred Demon enters the battlefield, search your library for a card, put it into your hand, then shuffle.

Kokusho, the Evening Star

Flying
When Kokusho, the Evening Star dies, each opponent loses 5 life. You gain life equal to the life lost this way.

Good-mini strat

Underworld Connections

Enchant land
Enchanted land has "{T}, Pay 1 life: Draw a card."

Savra, Queen of the Golgari

Whenever you sacrifice a black creature, you may pay 2 life. If you do, each other player sacrifices a creature.
Whenever you sacrifice a green creature, you may gain 2 life.

Craterhoof Behemoth

Haste
When Craterhoof Behemoth enters the battlefield, creatures you control gain trample and get +X/+X until end of turn, where X is the number of creatures you control.

Woodland Cemetery

Woodland Cemetery enters the battlefield tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Castle Garenbrig

Castle Garenbrig enters the battlefield tapped unless you control a Forest.
{T}: Add {G}.
{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

The Haunt of Hightower

Flying, lifelink
Whenever The Haunt of Hightower attacks, defending player discards a card.
Whenever a card is put into an opponent's graveyard from anywhere, put a +1/+1 counter on The Haunt of Hightower.

Emrakul's Evangel

{T}, Sacrifice Emrakul's Evangel and any number of other non-Eldrazi creatures: Create a 3/2 colorless Eldrazi Horror creature token for each creature sacrificed this way.

Cavalier of Thorns

Reach
When Cavalier of Thorns enters the battlefield, reveal the top five cards of your library. Put a land card from among them onto the battlefield and the rest into your graveyard.
When Cavalier of Thorns dies, you may exile it. If you do, put another target card from your graveyard on top of your library.

Everglades

Everglades enters the battlefield tapped.
When Everglades enters the battlefield, sacrifice it unless you return an untapped Swamp you control to its owner's hand.
{T}: Add {C}{B}.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Golgari Findbroker

When Golgari Findbroker enters the battlefield, return target permanent card from your graveyard to your hand.

I just like it

Scourge of Nel Toth

Flying
You may cast Scourge of Nel Toth from your graveyard by paying {B}{B} and sacrificing two creatures rather than paying its mana cost.

Blooming Marsh

Blooming Marsh enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {B} or {G}.

Garruk, Cursed Huntsman

0: Create two 2/2 black and green Wolf creature tokens with "When this creature dies, put a loyalty counter on each Garruk you control."
−3: Destroy target creature. Draw a card.
−6: You get an emblem with "Creatures you control get +3/+3 and have trample."

Treasured Find

Return target card from your graveyard to your hand. Exile Treasured Find.

Twilight Mire

{T}: Add {C}.
{B/G}, {T}: Add {B}{B}, {B}{G}, or {G}{G}.

Toxic Deluge

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

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Sandwurm Convergence

Creatures with flying can't attack you or planeswalkers you control.
At the beginning of your end step, create a 5/5 green Wurm creature token.

The Great Henge

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
{T}: Add {G}{G}. You gain 2 life.
Whenever a nontoken creature enters the battlefield under your control, put a +1/+1 counter on it and draw a card.

Same effect

Jarad, Golgari Lich Lord

Jarad, Golgari Lich Lord gets +1/+1 for each creature card in your graveyard.
{1}{B}{G}, Sacrifice another creature: Each opponent loses life equal to the sacrificed creature's power.
Sacrifice a Swamp and a Forest: Return Jarad from your graveyard to your hand.

Sidisi, Undead Vizier

Deathtouch
Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle.

Worm Harvest

Create a 1/1 black and green Worm creature token for each land card in your graveyard.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Shadowborn Demon

Flying
When Shadowborn Demon enters the battlefield, destroy target non-Demon creature.
At the beginning of your upkeep, if there are fewer than six creature cards in your graveyard, sacrifice a creature.

Questing Beast

Vigilance, deathtouch, haste
Questing Beast can't be blocked by creatures with power 2 or less.
Combat damage that would be dealt by creatures you control can't be prevented.
Whenever Questing Beast deals combat damage to an opponent, it deals that much damage to target planeswalker that player controls.

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Grave Titan

Deathtouch
Whenever Grave Titan enters the battlefield or attacks, create two 2/2 black Zombie creature tokens.

Meh - strat

Golgari Thug

When Golgari Thug dies, put target creature card from your graveyard on top of your library.
Dredge 4 (If you would draw a card, you may mill four cards instead. If you do, return this card from your graveyard to your hand.)

Ravenous Chupacabra

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

Lord of the Void

Flying
Whenever Lord of the Void deals combat damage to a player, exile the top seven cards of that player's library, then put a creature card from among them onto the battlefield under your control.

Noxious Gearhulk

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

Ormendahl, Profane Prince

Westvale Abbey

{T}: Add {C}.
{5}, {T}, Pay 1 life: Create a 1/1 white and black Human Cleric creature token.
{5}, {T}, Sacrifice five creatures: Transform Westvale Abbey, then untap it.

Westvale Abbey // Ormendahl, Profane Prince

Phyrexian Plaguelord

{T}, Sacrifice Phyrexian Plaguelord: Target creature gets -4/-4 until end of turn.
Sacrifice a creature: Target creature gets -1/-1 until end of turn.

Mycoloth

Devour 2 (As this enters the battlefield, you may sacrifice any number of creatures. This creature enters the battlefield with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Jungle Basin

Jungle Basin enters the battlefield tapped.
When Jungle Basin enters the battlefield, sacrifice it unless you return an untapped Forest you control to its owner's hand.
{T}: Add {C}{G}.

Vizier of the Menagerie

You may look at the top card of your library any time.
You may cast creature spells from the top of your library.
You can spend mana of any type to cast creature spells.

Mitotic Slime

When Mitotic Slime dies, create two 2/2 green Ooze creature tokens. They have "When this creature dies, create two 1/1 green Ooze creature tokens."

Sol Ring

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Black Market

Whenever a creature dies, put a charge counter on Black Market.
At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.

Forest

Massacre Wurm

When Massacre Wurm enters the battlefield, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Yahenni, Undying Partisan

Haste
Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.
Sacrifice another creature: Yahenni gains indestructible until end of turn.

Deathsprout

Destroy target creature. Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Tree of Perdition

Defender
{T}: Exchange target opponent's life total with Tree of Perdition's toughness.

Perilous Forays

{1}, Sacrifice a creature: Search your library for a land card with a basic land type, put it onto the battlefield tapped, then shuffle.

Sylvan Library

At the beginning of your draw step, you may draw two additional cards. If you do, choose two cards in your hand drawn this turn. For each of those cards, pay 4 life or put the card on top of your library.

Crucible of Worlds

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Falkenrath Noble

Flying
Whenever Falkenrath Noble or another creature dies, target player loses 1 life and you gain 1 life.

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Deadbridge Chant

When Deadbridge Chant enters the battlefield, mill ten cards.
At the beginning of your upkeep, choose a card at random in your graveyard. If it's a creature card, put it onto the battlefield. Otherwise, put it into your hand.

Sadistic Hypnotist

Sacrifice a creature: Target player discards two cards. Activate only as a sorcery.

Black Sun's Zenith

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Golgari Signet

Sisters of Stone Death

{G}: Target creature blocks Sisters of Stone Death this turn if able.
{B}{G}: Exile target creature blocking or blocked by Sisters of Stone Death.
{2}{B}: Put a creature card exiled with Sisters of Stone Death onto the battlefield under your control.

Windgrace's Judgment

For any number of opponents, destroy target nonland permanent that player controls.

Verdant Force

At the beginning of each upkeep, create a 1/1 green Saproling creature token.

Endrek Sahr, Master Breeder

Whenever you cast a creature spell, create X 1/1 black Thrull creature tokens, where X is that spell's mana value.
When you control seven or more Thrulls, sacrifice Endrek Sahr, Master Breeder.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Chittering Witch

When Chittering Witch enters the battlefield, create a number of 1/1 black Rat creature tokens equal to the number of opponents you have.
{1}{B}, Sacrifice a creature: Target creature gets -2/-2 until end of turn.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Storrev, Devkarin Lich

Trample
Whenever Storrev, Devkarin Lich deals combat damage to a player or planeswalker, return to your hand target creature or planeswalker card in your graveyard that wasn't put there this combat.

Hatchery Spider

Reach
Undergrowth — When you cast this spell, reveal the top X cards of your library, where X is the number of creature cards in your graveyard. You may put a green permanent card with mana value X or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Regrowth

Return target card from your graveyard to your hand.

Underrealm Lich

If you would draw a card, instead look at the top three cards of your library, then put one into your hand and the rest into your graveyard.
Pay 4 life: Underrealm Lich gains indestructible until end of turn. Tap it.

Fine - no strat

Attrition

{B}, Sacrifice a creature: Destroy target nonblack creature.

Pathbreaker Ibex

Whenever Pathbreaker Ibex attacks, creatures you control gain trample and get +X/+X until end of turn, where X is the greatest power among creatures you control.