Kraul Foragers

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

Swamp

Forest

Switch out?

Attendant of Vraska

When this creature dies, if you control a Vraska planeswalker, you gain life equal to this creature's power.

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.

Glass of the Guildpact

Multicolored creatures you control get +1/+1.

Undercity Upheaval

Undergrowth — Distribute X +1/+1 counters among any number of target creatures you control, where X is the number of creature cards in your graveyard as you cast this spell. Creatures you control gain vigilance until end of turn.

Ochran Assassin

Deathtouch
All creatures able to block this creature do so.

Moss-Pit Skeleton

Kicker {3} (You may pay an additional {3} as you cast this spell.)
If this creature was kicked, it enters with three +1/+1 counters on it.
Whenever one or more +1/+1 counters are put on a creature you control, if this card is in your graveyard, you may put this card on top of your library.

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.

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.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Spore Crawler

Radiant Fountain

When this land enters, you gain 2 life.
{T}: Add {C}.

Vraska's Stoneglare

Destroy target creature. You gain life equal to its toughness. You may search your library and/or graveyard for a card named Vraska, Regal Gorgon, reveal it, and put it into your hand. If you search your library this way, shuffle.

Glaive of the Guildpact

Equipped creature gets +1/+0 for each Gate you control and has vigilance and menace. (A creature with menace can't be blocked except by two or more creatures.)
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Stony Strength

Put a +1/+1 counter on target creature you control. Untap that creature.

Crawling Infestation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more creature cards are put into your graveyard from anywhere during your turn, create a 1/1 green Insect creature token. This ability triggers only once each turn.

Hired Poisoner

Skull Prophet

{T}: Add {B} or {G}.
{T}: Mill two cards. (Put the top two cards of your library into your graveyard.)

Glowspore Shaman

When this creature enters, mill three cards. You may put a land card from your graveyard on top of your library. (To mill a card, put the top card of your library into your graveyard.)

Obelisk Spider

Reach
Whenever this creature deals combat damage to a creature, put a -1/-1 counter on that creature.
Whenever you put one or more -1/-1 counters on a creature, each opponent loses 1 life and you gain 1 life.

Vraska, Regal Gorgon

+2: Put a +1/+1 counter on up to one target creature. That creature gains menace until end of turn.
−3: Destroy target creature.
−10: For each creature card in your graveyard, put a +1/+1 counter on each creature you control.

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.

Silhana Wayfinder

When this creature enters, look at the top four cards of your library. You may reveal a creature or land card from among them and put it on top of your library. Put the rest on the bottom of your library in a random order.

Prey Upon

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Lotleth Giant

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

Vraska the Unseen

+1: Until your next turn, whenever a creature deals combat damage to Vraska, destroy that creature.
−3: Destroy target nonland permanent.
−7: Create three 1/1 black Assassin creature tokens with "Whenever this token deals combat damage to a player, that player loses the game."

Gateway Plaza

This land enters tapped.
When this land enters, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Swarm Guildmage

{4}{B}, {T}: Creatures you control get +1/+0 and gain menace until end of turn. (They can't be blocked except by two or more creatures.)
{1}{G}, {T}: You gain 2 life.

Ironshell Beetle

When this creature enters, put a +1/+1 counter on target creature.

Golgari Guildgate

This land enters tapped.
{T}: Add {B} or {G}.

Gnarled Grovestrider

Vigilance
Other creatures you control have vigilance.

Dormant Grove

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has toughness 6 or greater, transform this enchantment.