Undergrowth Scavenger

This creature enters with a number of +1/+1 counters on it equal to the number of creature cards in all graveyards.

Svogthos, the Restless Tomb

{T}: Add {C}.
{3}{B}{G}: Until end of turn, this land becomes a black and green Plant Zombie creature with "This creature's power and toughness are each equal to the number of creature cards in your graveyard." It's still a land.

Liliana's Elite

This creature gets +1/+1 for each creature card in your graveyard.

Grist, the Hunger Tide

As long as Grist isn't on the battlefield, it's a 1/1 Insect creature in addition to its other types.
+1: Create a 1/1 black and green Insect creature token, then mill a card. If an Insect card was milled this way, put a loyalty counter on Grist and repeat this process.
−2: You may sacrifice a creature. When you do, destroy target creature or planeswalker.
−5: Each opponent loses life equal to the number of creature cards in your graveyard.

Jarad, Golgari Lich Lord

Jarad 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 this card from your graveyard to your hand.

Kraul Harpooner

Reach
Undergrowth — When this creature enters, choose up to one target creature you don't control with flying. This creature gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard, then you may have this creature fight that creature.

Fiend Artisan

This creature gets +1/+1 for each creature card in your graveyard.
{X}{B/G}, {T}, Sacrifice another creature: Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle. Activate only as a sorcery.

Lotleth Giant

Undergrowth — When this creature enters, it deals 1 damage to target opponent for each creature card in your graveyard.

Songs of the Damned

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

Nemesis of Mortals

This spell costs {1} less to cast for each creature card in your graveyard.
{7}{G}{G}: Monstrosity 5. This ability costs {1} less to activate for each creature card in your graveyard. (If this creature isn't monstrous, put five +1/+1 counters on it and it becomes monstrous.)

Moodmark Painter

Undergrowth — When this creature enters, target creature gains menace and gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard. (It can't be blocked except by two or more creatures.)

Seed Guardian

Reach
When this creature dies, create an X/X green Elemental creature token, where X is the number of creature cards in your graveyard.

Molderhulk

Undergrowth — This spell costs {1} less to cast for each creature card in your graveyard.
When this creature enters, return target land card from your graveyard to the battlefield.

Ghoultree

This spell costs {1} less to cast for each creature card in your graveyard.

Skull Prophet

{T}: Add {B} or {G}.
{T}: Mill two cards.

Splinterfright

Trample
Splinterfright's power and toughness are each equal to the number of creature cards in your graveyard.
At the beginning of your upkeep, mill two cards. (Put the top two cards of your library into your graveyard.)

Revenant

Flying
Revenant's power and toughness are each equal to the number of creature cards in your graveyard.

Graverobber Spider

Reach
{3}{B}: This creature gets +X/+X until end of turn, where X is the number of creature cards in your graveyard. Activate only once each turn.

Mausoleum Secrets

Undergrowth — Search your library for a black card with mana value less than or equal to the number of creature cards in your graveyard, reveal it, put it into your hand, then shuffle.

Kessig Cagebreakers

Whenever this creature attacks, create a 2/2 green Wolf creature token that's tapped and attacking for each creature card in your graveyard.

Izoni, Thousand-Eyed

Undergrowth — When Izoni enters, create a 1/1 black and green Insect creature token for each creature card in your graveyard.
{B}{G}, Sacrifice another creature: You gain 1 life and draw a card.

Rhizome Lurcher

Undergrowth — This creature enters with a number of +1/+1 counters on it equal to the number of creature cards in your graveyard.

Boneyard Wurm

Boneyard Wurm's power and toughness are each equal to the number of creature cards in your graveyard.

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: This creature gains indestructible until end of turn. Tap it.

Grave Strength

Choose target creature. Mill three cards, then put a +1/+1 counter on that creature for each creature card in your graveyard. (To mill three cards, put the top three cards of your library into your graveyard.)

Old Stickfingers

When you cast this spell, reveal cards from the top of your library until you reveal X creature cards. Put all creature cards revealed this way into your graveyard, then put the rest on the bottom of your library in a random order.
Old Stickfingers's power and toughness are each equal to the number of creature cards in your graveyard.

Necrotic Wound

Undergrowth — Target creature gets -X/-X until end of turn, where X is the number of creature cards in your graveyard. If that creature would die this turn, exile it instead.

Golgari Grave-Troll

This creature enters with a +1/+1 counter on it for each creature card in your graveyard.
{1}, Remove a +1/+1 counter from this creature: Regenerate this creature.
Dredge 6 (If you would draw a card, you may mill six cards instead. If you do, return this card from your graveyard to your hand.)

Grim Flowering

Draw a card for each creature card in your graveyard.

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.

Graveblade Marauder

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever this creature deals combat damage to a player, that player loses life equal to the number of creature cards in your graveyard.

Golgari Raiders

Haste
Undergrowth — This creature enters with a +1/+1 counter on it for each creature card in your graveyard.

Kraul Foragers

Undergrowth — When this creature enters, you gain 1 life for each creature card in your graveyard.

Vigorspore Wurm

Undergrowth — When this creature enters, target creature gains vigilance and gets +X/+X until end of turn, where X is the number of creature cards in your graveyard.
This creature can't be blocked by more than one creature.

Ghoul's Feast

Target creature gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard.

Wreath of Geists

Enchant creature
Enchanted creature gets +X/+X, where X is the number of creature cards in your graveyard.

Spider Spawning

Create a 1/2 green Spider creature token with reach for each creature card in your graveyard.
Flashback {6}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ghoulcaller's Harvest

Create X 2/2 black Zombie creature tokens with decayed, where X is half the number of creature cards in your graveyard, rounded up. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)
Flashback {3}{B}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)