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}

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Manascape Refractor

This artifact enters tapped.
This artifact has all activated abilities of all lands on the battlefield.
You may spend mana as though it were mana of any color to pay the activation costs of this artifact's abilities.

Dark Depths

Dark Depths enters with ten ice counters on it.
{3}: Remove an ice counter from Dark Depths.
When Dark Depths has no ice counters on it, sacrifice it. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

Tyrite Sanctum

{T}: Add {C}.
{2}, {T}: Target legendary creature becomes a God in addition to its other types. Put a +1/+1 counter on it.
{4}, {T}, Sacrifice this land: Put an indestructible counter on target God.

Maze's End

This land enters tapped.
{T}: Add {C}.
{3}, {T}, Return this land to its owner's hand: Search your library for a Gate card, put it onto the battlefield, then shuffle. If you control ten or more Gates with different names, you win the game.

Sol Ring

Basilisk Gate

{T}: Add {C}.
{2}, {T}: Target creature gets +X/+X until end of turn, where X is the number of Gates you control. Activate only as a sorcery.

Crucible of Worlds

Accursed Duneyard

{T}: Add {C}.
{2}, {T}: Regenerate target Shade, Skeleton, Specter, Spirit, Vampire, Wraith, or Zombie. (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Reliquary Tower

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

Thespian's Stage

{T}: Add {C}.
{2}, {T}: This land becomes a copy of target land, except it has this ability.

March from Velis Vel

Choose a nonbasic land type. Each land you control of that type becomes a copy of target creature you control until end of turn and gains haste until end of turn.
Flashback {4}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Myr Galvanizer

Other Myr creatures you control get +1/+1.
{1}, {T}: Untap each other Myr you control.

Uro, Titan of Nature's Wrath

When Uro enters, sacrifice it unless it escaped.
Whenever Uro enters or attacks, you gain 3 life and draw a card, then you may put a land card from your hand onto the battlefield.
Escape—{G}{G}{U}{U}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Seshiro the Anointed

Other Snake creatures you control get +2/+2.
Whenever a Snake you control deals combat damage to a player, you may draw a card.

Secluded Courtyard

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

Gallifrey Council Chamber

When Gallifrey Council Chamber enters, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Time Lord or Alien spell or activate an ability of a Time Lord or Alien.

Dwynen, Gilt-Leaf Daen

Reach (This creature can block creatures with flying.)
Other Elf creatures you control get +1/+1.
Whenever Dwynen attacks, you gain 1 life for each attacking Elf you control.

Sea Gate Loremaster

{T}: Draw a card for each Ally you control.

Thran Portal

This land enters tapped unless you control two or fewer other lands.
As this land enters, choose a basic land type.
This land is the chosen type in addition to its other types.
Mana abilities of this land cost an additional 1 life to activate.

Pheres-Band Warchief

Vigilance, trample
Other Centaur creatures you control get +1/+1 and have vigilance and trample.

Vesuva

You may have this land enter tapped as a copy of any land on the battlefield.

Elvish Archdruid

Other Elf creatures you control get +1/+1.
{T}: Add {G} for each Elf you control.

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Tatyova, Benthic Druid

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

Feline Sovereign

Other Cats you control get +1/+1 and have protection from Dogs.
Whenever one or more Cats you control deal combat damage to a player, destroy up to one target artifact or enchantment that player controls.

Thunderfoot Baloth

Trample
Lieutenant — As long as you control your commander, this creature gets +2/+2 and other creatures you control get +2/+2 and have trample.

Aesi, Tyrant of Gyre Strait

You may play an additional land on each of your turns.
Landfall — Whenever a land you control enters, you may draw a card.

Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Urborg, Tomb of Yawgmoth

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

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Merfolk Sovereign

Other Merfolk creatures you control get +1/+1.
{T}: Target Merfolk creature can't be blocked this turn.

Whelming Wave

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Manaweft Sliver

Sliver creatures you control have "{T}: Add one mana of any color."

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Multiclass Baldric

Equipped creature has lifelink if you control a Cleric, deathtouch if you control a Rogue, haste if you control a Warrior, and flying if you control a Wizard.
As long as you have a full party, prevent all damage that would be dealt to equipped creature.
Equip {2}

Megantic Sliver

Baldur's Gate

{T}: Add {C}.
{2}, {T}: Add X mana of any one color, where X is the number of other Gates you control.

Finale of Revelation

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.
Exile Finale of Revelation.

Elvish Champion

Other Elf creatures get +1/+1 and have forestwalk. (They can't be blocked as long as defending player controls a Forest.)

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Island

Ulvenwald Hydra

Reach
Ulvenwald Hydra's power and toughness are each equal to the number of lands you control.
When this creature enters, you may search your library for a land card, put it onto the battlefield tapped, then shuffle.

Roaming Throne

Ward {2}
As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Alchemist's Refuge

{T}: Add {C}.
{G}{U}, {T}: You may cast spells this turn as though they had flash.

Priest of Titania

{T}: Add {G} for each Elf on the battlefield.

Forest

Nissa, Steward of Elements

+2: Scry 2.
0: Look at the top card of your library. If it's a land card or a creature card with mana value less than or equal to the number of loyalty counters on Nissa, you may put that card onto the battlefield.
−6: Untap up to two target lands you control. They become 5/5 Elemental creatures with flying and haste until end of turn. They're still lands.

Omo, Queen of Vesuva

Whenever Omo enters or attacks, put an everything counter on each of up to one target land and up to one target creature.
Each land with an everything counter on it is every land type in addition to its other types.
Each nonland creature with an everything counter on it is every creature type.

Lord of the Unreal

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Fecund Greenshell

Reach
As long as you control ten or more lands, creatures you control get +2/+2.
Whenever this creature or another creature you control with toughness greater than its power enters, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped. Otherwise, put it into your hand.

Dazzling Denial

Counter target spell unless its controller pays {2}. If you control a Bird, counter that spell unless its controller pays {4} instead.

Jyoti, Moag Ancient

When Jyoti enters, create a 1/1 green Forest Dryad land creature token for each time you've cast your commander from the command zone this game. (They're affected by summoning sickness.)
At the beginning of each combat, land creatures you control get +X/+X until end of turn, where X is Jyoti's power.

Swarmyard

{T}: Add {C}.
{T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Baru, Wurmspeaker

Wurms you control get +2/+2 and have trample.
{7}{G}, {T}: Create a 4/4 green Wurm creature token. This ability costs {X} less to activate, where X is the greatest power among Wurms you control.

Riptide Laboratory

{T}: Add {C}.
{1}{U}, {T}: Return target Wizard you control to its owner's hand.

Urza's Cave

{T}: Add {C}.
{3}, {T}, Sacrifice this land: Search your library for a land card, put it onto the battlefield tapped, then shuffle.

Urza's Factory

{T}: Add {C}.
{7}, {T}: Create a 2/2 colorless Assembly-Worker artifact creature token.

Aggressive Biomancy

Create X tokens that are copies of target creature you control, except they have "When this token enters, it fights up to one target creature you don't control."

Vanquisher's Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Glimmerpost

When this land enters, you gain 1 life for each Locus on the battlefield.
{T}: Add {C}.

Brotherhood Headquarters

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast an Assassin spell or a spell that has freerunning, or to activate an ability of an Assassin source.

Patchwork Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Urza's Workshop

{T}: Add {C}.
Metalcraft — {T}: Add {C} for each Urza's land you control. Activate only if you control three or more artifacts.

Herald of Hoofbeats

Horsemanship (This creature can't be blocked except by creatures with horsemanship.)
Other Knights you control have horsemanship.

Master of the Pearl Trident

Other Merfolk creatures you control get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

Homeward Path

{T}: Add {C}.
{T}: Each player gains control of all creatures they own.

Venom Sliver

Sliver creatures you control have deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Tempt with Discovery

Tempting offer — Search your library for a land card and put it onto the battlefield. Each opponent may search their library for a land card and put it onto the battlefield. For each opponent who searches a library this way, search your library for a land card and put it onto the battlefield. Then each player who searched a library this way shuffles.

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice this land: You may cast spells this turn as though they had flash.

Galerider Sliver

Sliver creatures you control have flying.

Nissa, Who Shakes the World

Whenever you tap a Forest for mana, add an additional {G}.
+1: Put three +1/+1 counters on up to one target noncreature land you control. Untap it. It becomes a 0/0 Elemental creature with vigilance and haste that's still a land.
−8: You get an emblem with "Lands you control have indestructible." Search your library for any number of Forest cards, put them onto the battlefield tapped, then shuffle.

Scion of Oona

Flash
Flying
Other Faerie creatures you control get +1/+1.
Other Faeries you control have shroud. (They can't be the targets of spells or abilities.)

Harabaz Druid

{T}: Add X mana of any one color, where X is the number of Allies you control.

Diffusion Sliver

Whenever a Sliver creature you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.

Forgotten Cellar

When you unlock this door, you may cast spells from your graveyard this turn, and if a card would be put into your graveyard from anywhere this turn, exile it instead.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Walk-In Closet

You may play lands from your graveyard.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Walk-In Closet // Forgotten Cellar

Circuitous Route

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.

Scute Swarm

Landfall — Whenever a land you control enters, create a 1/1 green Insect creature token. If you control six or more lands, create a token that's a copy of this creature instead.

Yavimaya, Cradle of Growth

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

Travel the Overworld

Affinity for Towns (This spell costs {1} less to cast for each Town you control.)
Draw four cards.

Cyclone Summoner

When this creature enters, if you cast it from your hand, return all permanents to their owners' hands except for Giants, Wizards, and lands.

Timber Protector

Other Treefolk creatures you control get +1/+1.
Other Treefolk and Forests you control have indestructible.

Hakbal of the Surging Soul

At the beginning of combat on your turn, each Merfolk creature you control 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 exploring creature, then put the card back or put it into your graveyard.)
Whenever Hakbal attacks, you may put a land card from your hand onto the battlefield. If you don't, draw a card.

Arcane Signet

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

Strix Serenade

Counter target artifact, creature, or planeswalker spell. Its controller creates a 2/2 blue Bird creature token with flying.