The Watcher in the Water

The Watcher in the Water enters tapped with nine stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you draw a card during an opponent's turn, create a 1/1 blue Tentacle creature token.
Whenever a Tentacle you control dies, untap up to one target Kraken and put a stun counter on up to one target nonland permanent.

Uyo, Silent Prophet

Flying
{2}, Return two lands you control to their owner's hand: Copy target instant or sorcery spell. You may choose new targets for the copy.

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.

Walking Atlas

{T}: You may put a land card from your hand onto the battlefield.

Trade Routes

{1}: Return target land you control to its owner's hand.
{1}, Discard a land card: Draw a card.

Vapor Snare

Enchant creature
You control enchanted creature.
At the beginning of your upkeep, sacrifice this Aura unless you return a land you control to its owner's hand.

Case of the Locked Hothouse

You may play an additional land on each of your turns.
To solve — You control seven or more lands. (If unsolved, solve at the beginning of your end step.)
Solved — You may look at the top card of your library any time, and you may play lands and cast creature and enchantment spells from the top of your library.

Spectrum Sentinel

Protection from multicolored (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything multicolored.)
Whenever a nonbasic land an opponent controls enters, you gain 1 life.

Hardy Outlander

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, another target creature you control gets +X/+X until end of turn, where X is this creature's power."

Land Equilibrium

If an opponent who controls at least as many lands as you do would put a land onto the battlefield, that player instead puts that land onto the battlefield then sacrifices a land of their choice.

Sophia, Dogged Detective

When Sophia enters, create Tiny, a legendary 2/2 green Dog Detective creature token with trample.
{1}, Sacrifice an artifact token: Put a +1/+1 counter on each Dog you control.
Whenever a Dog you control deals combat damage to a player, create a Food token, then investigate.

Crop Sigil

At the beginning of your upkeep, you may mill a card.
Delirium — {2}{G}, Sacrifice this enchantment: Return up to one target creature card and up to one target land card from your graveyard to your hand. Activate only if there are four or more card types among cards in your graveyard.

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Noble Heritage

Commander creatures you own have "When this creature enters and at the beginning of your upkeep, each player may put two +1/+1 counters on a creature they control. For each opponent who does, you gain protection from that player until your next turn." (You can't be targeted, dealt damage, or enchanted by anything controlled by that player.)

Trench Behemoth

Return a land you control to its owner's hand: Untap this creature. It gains hexproof until end of turn.
Landfall — Whenever a land you control enters, target creature an opponent controls attacks during its controller's next combat phase if able.

Nissa, Sage Animist

+1: Reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.
−2: Create Ashaya, the Awoken World, a legendary 4/4 green Elemental creature token.
−7: Untap up to six target lands. They become 6/6 Elemental creatures. They're still lands.

Nissa, Vastwood Seer

When Nissa enters, you may search your library for a basic Forest card, reveal it, put it into your hand, then shuffle.
Whenever a land you control enters, if you control seven or more lands, exile Nissa, then return her to the battlefield transformed under her owner's control.

Nissa, Vastwood Seer // Nissa, Sage Animist

K-9, Mark I

Negative — As long as K-9 is untapped, other legendary creatures you control have ward {1}.
Affirmative — {1}{U}, {T}: Target legendary creature can't be blocked this turn.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Tiny

Trap Digger

{2}{W}, {T}: Put a trap counter on target land you control.
Sacrifice a land with a trap counter on it: This creature deals 3 damage to target attacking creature without flying.

Redrock Sentinel

Defender
{2}, {T}, Sacrifice a land: Draw a card and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Watchdog

This creature blocks each combat if able.
As long as this creature is untapped, all creatures attacking you get -1/-0.

Iron Mastiff

Whenever this creature attacks, roll a d20 for each player being attacked and ignore all but the highest roll.
1—9 | This creature deals damage equal to its power to you.
10—19 | This creature deals damage equal to its power to defending player.
20 | This creature deals damage equal to its power to each opponent.

Loamcrafter Faun

When this creature enters, you may discard one or more land cards. When you do, return up to that many target nonland permanent cards from your graveyard to your hand.

Wonderscape Sage

Flying
{T}, Return a land you control to its owner's hand: Draw a card. Then discard a card unless that land had a nonbasic land type.

Elven Warhounds

Whenever this creature becomes blocked by a creature, put that creature on top of its owner's library.

Folk Hero

Commander creatures you own have "Whenever you cast a spell that shares a creature type with this creature, draw a card. This ability triggers only once each turn."

Yoshimaru, Ever Faithful

Whenever another legendary permanent you control enters, put a +1/+1 counter on Yoshimaru.
Partner (You can have two commanders if both have partner.)

The Reality Chip

You may look at the top card of your library any time.
As long as The Reality Chip is attached to a creature, you may play lands and cast spells from the top of your library.
Reconfigure {2}{U} ({2}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Floodhound

{3}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Zuran Orb

Thrasios, Triton Hero

{4}: Scry 1, then reveal the top card of your library. If it's a land card, put it onto the battlefield tapped. Otherwise, draw a card.
Partner (You can have two commanders if both have partner.)

Sandstone Deadfall

{T}, Sacrifice two lands and this artifact: Destroy target attacking creature.

Mordenkainen

+2: Draw two cards, then put a card from your hand on the bottom of your library.
−2: Create a blue Dog Illusion creature token with "This token's power and toughness are each equal to twice the number of cards in your hand."
−10: Exchange your hand and library, then shuffle. You get an emblem with "You have no maximum hand size."

Master Chef

Commander creatures you own have "This creature enters with an additional +1/+1 counter on it" and "Other creatures you control enter with an additional +1/+1 counter on them."

Nissa's Zendikon

Enchant land
Enchanted land is a 4/4 Elemental creature with reach and haste. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Wind Zendikon

Enchant land
Enchanted land is a 2/2 blue Elemental creature with flying. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Spitting Spider

Reach (This creature can block creatures with flying.)
Sacrifice a land: This creature deals 1 damage to each creature with flying.

Pack Leader

Other Dogs you control get +1/+1.
Whenever this creature attacks, prevent all combat damage that would be dealt this turn to Dogs you control.

Basilisk Collar

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Meloku the Clouded Mirror

Flying
{1}, Return a land you control to its owner's hand: Create a 1/1 blue Illusion creature token with flying.

Aura Fracture

Sacrifice a land: Destroy target enchantment.

Phelia, Exuberant Shepherd

Flash
Whenever Phelia attacks, exile up to one other target nonland permanent. At the beginning of the next end step, return that card to the battlefield under its owner's control. If it entered under your control, put a +1/+1 counter on Phelia.

Oboro Breezecaller

Flying
{2}, Return a land you control to its owner's hand: Untap target land.

Tiller Engine

Whenever a land you control enters tapped, choose one —
• Untap that land.
• Tap target nonland permanent an opponent controls.

Sylvan Safekeeper

Sacrifice a land: Target creature you control gains shroud until end of turn. (It can't be the target of spells or abilities.)

Ancient Greenwarden

Reach (This creature can block creatures with flying.)
You may play lands from your graveyard.
If a land entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Soratami Mirror-Mage

Flying
{3}, Return three lands you control to their owner's hand: Return target creature to its owner's hand.

Earthquake Dragon

This spell costs {X} less to cast, where X is the total mana value of Dragons you control.
Flying, trample
{2}{G}, Sacrifice a land: Return this card from your graveyard to your hand.

Roots of Life

As this enchantment enters, choose Island or Swamp.
Whenever a land of the chosen type an opponent controls becomes tapped, you gain 1 life.

Far Traveler

Commander creatures you own have "At the beginning of your end step, exile up to one target tapped creature you control, then return it to the battlefield under its owner's control."

Rex, Cyber-Hound

Whenever Rex deals combat damage to a player, they mill two cards and you get {E}{E} (two energy counters).
Pay {E}{E}: Choose target creature card in a graveyard. Exile it with a brain counter on it. Activate only as a sorcery.
Rex has all activated abilities of all cards in exile with brain counters on them.

Mana Breach

Whenever a player casts a spell, that player returns a land they control to its owner's hand.

Burgeoning

Whenever an opponent plays a land, you may put a land card from your hand onto the battlefield.

Shattered Angel

Flying
Whenever a land an opponent controls enters, you may gain 3 life.

Tameshi, Reality Architect

Whenever one or more noncreature permanents are returned to hand, draw a card. This ability triggers only once each turn.
{X}{W}, Return a land you control to its owner's hand: Return target artifact or enchantment card with mana value X or less from your graveyard to the battlefield. Activate only as a sorcery.

Tanuki Transplanter

Whenever this creature or equipped creature attacks, add an amount of {G} equal to its power. Until end of turn, you don't lose this mana as steps and phases end.
Reconfigure {3} ({3}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Soratami Cloudskater

Flying
{2}, Return a land you control to its owner's hand: Draw a card, then discard a card.

Mowu

Mowu // Mowu

Elvish Reclaimer

This creature gets +2/+2 as long as there are three or more land cards in your graveyard.
{2}, {T}, Sacrifice a land: Search your library for a land card, put it onto the battlefield tapped, then shuffle.

Guardian Zendikon

Enchant land
Enchanted land is a 2/6 white Wall creature with defender. It's still a land.
When enchanted land dies, return that card to its owner's hand.

Jiang Yanggu

+1: Target creature gets +2/+2 until end of turn.
−1: If you don't control a creature named Mowu, create Mowu, a legendary 3/3 green Dog creature token.
−5: Until end of turn, target creature gains trample and gets +X/+X, where X is the number of lands you control.

Weathered Wayfarer

{W}, {T}: Search your library for a land card, reveal it, put it into your hand, then shuffle. Activate only if an opponent controls more lands than you.

Pegasus Stampede

Buyback—Sacrifice a land. (You may sacrifice a land in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Create a 1/1 white Pegasus creature token with flying.

Soratami Rainshaper

Flying
{3}, Return a land you control to its owner's hand: Target creature you control gains shroud until end of turn. (It can't be the target of spells or abilities.)

Exploration

You may play an additional land on each of your turns.

Crop Rotation

As an additional cost to cast this spell, sacrifice a land.
Search your library for a land card, put that card onto the battlefield, then shuffle.

Urban Burgeoning

Enchant land
Enchanted land has "Untap this land during each other player's untap step."