Urborg, Tomb of Yawgmoth

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

Path of Discovery

Whenever a creature you control enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)

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.)

Titans' Nest

At the beginning of your upkeep, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
Exile a card from your graveyard: Add {C}. Spend this mana only to cast a spell that's one or more colors without {X} in its mana cost.

World Shaper

Whenever World Shaper attacks, you may mill three cards.
When World Shaper dies, return all land cards from your graveyard to the battlefield tapped.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

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.

Loaming Shaman

When Loaming Shaman enters, target player shuffles any number of target cards from their graveyard into their library.

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Field of the Dead

Field of the Dead enters tapped.
{T}: Add {C}.
Whenever Field of the Dead or another land you control enters, if you control seven or more lands with different names, create a 2/2 black Zombie creature token.

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ashnod's Altar

Crawling Sensation

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 land cards are put into your graveyard from anywhere for the first time each turn, create a 1/1 green Insect creature token.

Opulent Palace

Opulent Palace enters tapped.
{T}: Add {B}, {G}, or {U}.

Nyx Weaver

Reach
At the beginning of your upkeep, mill two cards. (Put the top two cards of your library into your graveyard.)
{1}{B}{G}, Exile Nyx Weaver: Return target card from your graveyard to your hand.

Sol Ring

Unbound Flourishing

Whenever you cast a permanent spell with a mana cost that contains {X}, double the value of X.
Whenever you cast an instant or sorcery spell or activate an ability, if that spell's mana cost or that ability's activation cost contains {X}, copy that spell or ability. You may choose new targets for the copy.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Island

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.

Filth

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as Filth is in your graveyard and you control a Swamp, creatures you control have swampwalk.

Woodland Cemetery

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

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Undergrowth Stadium

Undergrowth Stadium enters tapped unless you have two or more opponents.
{T}: Add {B} or {G}.

Zagoth Triome

({T}: Add {B}, {G}, or {U}.)
Zagoth Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Jarad's Orders

Search your library for up to two creature cards and reveal them. Put one into your hand and the other into your graveyard. Then shuffle.

Rejuvenating Springs

Rejuvenating Springs enters tapped unless you have two or more opponents.
{T}: Add {G} or {U}.

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Muldrotha, the Gravetide

During each of your turns, you may play a land and cast a permanent spell of each permanent type from your graveyard. (If a card has multiple permanent types, choose one as you play it.)

Living Death

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

Kodama's Reach

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.

Cultivate

The Mending of Dominaria

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Mill two cards, then you may return a creature card from your graveyard to your hand.
III — Return all land cards from your graveyard to the battlefield, then shuffle your graveyard into your library.

Cabal Coffers

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

Entomb

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

Riftsweeper

When Riftsweeper enters, choose target face-up exiled card. Its owner shuffles it into their library.

Sidisi, Brood Tyrant

Whenever Sidisi, Brood Tyrant enters or attacks, mill three cards.
Whenever one or more creature cards are put into your graveyard from your library, create a 2/2 black Zombie creature token.

Brawn

Trample
As long as Brawn is in your graveyard and you control a Forest, creatures you control have trample.

Drownyard Temple

{T}: Add {C}.
{3}: Return Drownyard Temple from your graveyard to the battlefield tapped.

Runic Repetition

Return target exiled card with flashback you own to your hand.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

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.)

Gravecrawler

Gravecrawler can't block.
You may cast Gravecrawler from your graveyard as long as you control a Zombie.

Evolving Wilds

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

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Vilespawn Spider

Reach
At the beginning of your upkeep, mill a card. (Put the top card of your library into your graveyard.)
{2}{G}{U}, {T}, Sacrifice Vilespawn Spider: Create a 1/1 green Insect creature token for each creature card in your graveyard. Activate only as a sorcery.

Memory's Journey

Target player shuffles up to three target cards from their graveyard into their library.
Flashback {G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Reliquary Tower

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

Kruphix, God of Horizons

Indestructible
As long as your devotion to green and blue is less than seven, Kruphix isn't a creature.
You have no maximum hand size.
If you would lose unspent mana, that mana becomes colorless instead.

Forest

Toxic Deluge

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

Buried Alive

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

Svogthos, the Restless Tomb

{T}: Add {C}.
{3}{B}{G}: Until end of turn, Svogthos, the Restless Tomb 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.

Millikin

Out of the Tombs

At the beginning of your upkeep, put two eon counters on Out of the Tombs, then mill cards equal to the number of eon counters on it.
If you would draw a card while your library has no cards in it, instead return a creature card from your graveyard to the battlefield. If you can't, you lose the game.

Wonder

Flying
As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.

Dryad Arbor

(Dryad Arbor isn't a spell, it's affected by summoning sickness, and it has "{T}: Add {G}.")

Angel of Suffering

Flying
If damage would be dealt to you, prevent that damage and mill twice that many cards.

Zellix, Sanity Flayer

Hive Mind — Whenever a player mills one or more creature cards, you create a 1/1 black Horror creature token.
{1}, {T}: Target player mills three cards.
Choose a Background (You can have a Background as a second commander.)

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.

Ramunap Excavator

Embalmer's Tools

Activated abilities of creature cards in your graveyard cost {1} less to activate.
Tap an untapped Zombie you control: Target player mills a card.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Corpse Churn

Mill three cards, then you may return a creature card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)

Command Tower

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Sultai Ascendancy

At the beginning of your upkeep, 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.)

Conduit of Worlds

You may play lands from your graveyard.
{T}: Choose target nonland permanent card in your graveyard. If you haven't cast a spell this turn, you may cast that card. If you do, you can't cast additional spells this turn. Activate only as a sorcery.

Deathbloom Ritualist

{T}: Add X mana of any one color, where X is the number of creature cards in your graveyard.

Terramorphic Expanse

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

Mulch

Reveal the top four cards of your library. Put all land cards revealed this way into your hand and the rest into your graveyard.

Villainous Wealth

Target opponent exiles the top X cards of their library. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Kozilek, Butcher of Truth

When you cast this spell, draw four cards.
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents.)
When Kozilek, Butcher of Truth is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Yavimaya, Cradle of Growth

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

Sultai Charm

Choose one —
• Destroy target monocolored creature.
• Destroy target artifact or enchantment.
• Draw two cards, then discard a card.

Diregraf Captain

Deathtouch
Other Zombie creatures you control get +1/+1.
Whenever another Zombie you control dies, target opponent loses 1 life.

Demonic Tutor

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

Bojuka Bog

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

Swamp

Cemetery Tampering

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
At the beginning of your upkeep, you may mill three cards. Then if there are twenty or more cards in your graveyard, you may play the exiled card without paying its mana cost.