Urborg, Tomb of Yawgmoth

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

Lotleth Troll

Trample
Discard a creature card: Put a +1/+1 counter on Lotleth Troll.
{B}: Regenerate Lotleth Troll.

Pithing Needle

As Pithing Needle enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Tormod's Crypt

{T}, Sacrifice Tormod's Crypt: Exile target player's graveyard.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Soul-Guide Lantern

When this artifact enters, exile target card from a graveyard.
{T}, Sacrifice this artifact: Exile each opponent's graveyard.
{1}, {T}, Sacrifice this artifact: Draw a card.

Bone Shards

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

Finale of Devastation

Search your library and/or graveyard for a creature card with mana value X or less and put it onto the battlefield. If you search your library this way, shuffle. If X is 10 or more, creatures you control get +X/+X and gain haste until end of turn.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Feasting Troll King

Vigilance, trample
When Feasting Troll King enters, if you cast it from your hand, create three Food tokens. (They're artifacts with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Sacrifice three Foods: Return Feasting Troll King from your graveyard to the battlefield. Activate only during your turn.

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.

Ovalchase Daredevil

Whenever an artifact you control enters, you may return Ovalchase Daredevil from your graveyard to your hand.

Asmoranomardicadaistinaculdacar

As long as you've discarded a card this turn, you may pay {B/R} to cast this spell.
When Asmoranomardicadaistinaculdacar enters, you may search your library for a card named The Underworld Cookbook, reveal it, put it into your hand, then shuffle.
Sacrifice two Foods: Target creature deals 6 damage to itself.

Scavenging Ooze

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on this creature and you gain 1 life.

Blooming Marsh

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

Street Wraith

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Cycling—Pay 2 life. (Pay 2 life, Discard this card: Draw a card.)

Swamp

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Kroxa, Titan of Death's Hunger

When Kroxa enters, sacrifice it unless it escaped.
Whenever Kroxa enters or attacks, each opponent discards a card, then each opponent who didn't discard a nonland card this way loses 3 life.
Escape—{B}{B}{R}{R}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters, you may pay 2 life. If you don't, it enters tapped.

Gilded Goose

Flying
When Gilded Goose enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
{1}{G}, {T}: Create a Food token.
{T}, Sacrifice a Food: Add one mana of any color.

Witch's Oven

{T}, Sacrifice a creature: Create a Food token. If the sacrificed creature's toughness was 4 or greater, create two Food tokens instead. (They're artifacts with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

The Underworld Cookbook

{T}, Discard a card: Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
{4}, {T}, Sacrifice The Underworld Cookbook: Return target creature card from your graveyard to your hand.

Force of Vigor

If it's not your turn, you may exile a green card from your hand rather than pay this spell's mana cost.
Destroy up to two target artifacts and/or enchantments.

Yavimaya, Cradle of Growth

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

Forest

Cauldron Familiar

When Cauldron Familiar enters, each opponent loses 1 life and you gain 1 life.
Sacrifice a Food: Return Cauldron Familiar from your graveyard to the battlefield.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.