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.

Expedition Map

{2}, {T}, Sacrifice this artifact: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Reshape the Earth

Search your library for up to ten land cards, put them onto the battlefield tapped, then shuffle.

Undergrowth Champion

If damage would be dealt to this creature while it has a +1/+1 counter on it, prevent that damage and remove a +1/+1 counter from this creature.
Landfall — Whenever a land you control enters, put a +1/+1 counter on this creature.

Elemental Bond

Whenever a creature you control with power 3 or greater enters, draw a card.

Yavimaya, Cradle of Growth

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

Wrenn and Six

+1: Return up to one target land card from your graveyard to your hand.
−1: Wrenn and Six deals 1 damage to any target.
−7: You get an emblem with "Instant and sorcery cards in your graveyard have retrace." (You may cast instant and sorcery cards from your graveyard by discarding a land card in addition to paying their other costs.)

Evolving Wilds

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

Forgotten Ancient

Whenever a player casts a spell, you may put a +1/+1 counter on this creature.
At the beginning of your upkeep, you may move any number of +1/+1 counters from this creature onto other creatures.

Greenwarden of Murasa

When this creature enters, you may return target card from your graveyard to your hand.
When this creature dies, you may exile it. If you do, return target card from your graveyard to your hand.

Zendikar's Roil

Landfall — Whenever a land you control enters, create a 2/2 green Elemental creature token.

Mountain

Explore

You may play an additional land this turn.
Draw a card.

Forest

Mina and Denn, Wildborn

You may play an additional land on each of your turns.
{R}{G}, Return a land you control to its owner's hand: Target creature gains trample until end of turn.

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.

Decimate

Destroy target artifact, target creature, target enchantment, and target land. (You can't cast this spell unless you have legal choices for all its targets.)

Cinder Glade

({T}: Add {R} or {G}.)
This land enters tapped unless you control two or more basic lands.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Multani, Yavimaya's Avatar

Reach, trample
Multani gets +1/+1 for each land you control and each land card in your graveyard.
{1}{G}, Return two lands you control to their owner's hand: Return this card from your graveyard to your hand.

Cultivate

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.

Kamahl's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Until end of turn, any number of target lands you control become 1/1 Elemental creatures with vigilance, indestructible, and haste. They're still lands.
• Choose target creature you don't control. Each creature you control deals damage equal to its power to that creature.

Garruk's Uprising

When this enchantment enters, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever a creature you control with power 4 or greater enters, draw a card.

Perilous Forays

{1}, Sacrifice a creature: Search your library for a land card with a basic land type, put it onto the battlefield tapped, then shuffle.

Ingot Chewer

When this creature enters, destroy target artifact.
Evoke {R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Amulet of Vigor

Whenever a permanent you control enters tapped, untap it.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

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.

Azusa, Lost but Seeking

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

Avenger of Zendikar

When this creature enters, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land you control enters, you may put a +1/+1 counter on each Plant creature you control.

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Titania, Protector of Argoth

When Titania enters, return target land card from your graveyard to the battlefield.
Whenever a land you control is put into a graveyard from the battlefield, create a 5/3 green Elemental creature token.

Hull Breach

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Destroy target artifact and target enchantment.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Prismatic Vista

{T}, Pay 1 life, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Khalni Heart Expedition

Landfall — Whenever a land you control enters, you may put a quest counter on this enchantment.
Remove three quest counters from this enchantment and sacrifice it: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Commercial District

({T}: Add {R} or {G}.)
This land enters tapped.
When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Mountain Valley

This land enters tapped.
{T}, Sacrifice this land: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Praetor's Counsel

Return all cards from your graveyard to your hand. Exile Praetor's Counsel. You have no maximum hand size for the rest of the game.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

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.

Where Ancients Tread

Whenever a creature you control with power 5 or greater enters, you may have this enchantment deal 5 damage to any target.

Valakut, the Molten Pinnacle

This land enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target.
{T}: Add {R}.

Living Twister

{1}{R}, Discard a land card: This creature deals 2 damage to any target.
{G}: Return a tapped land you control to its owner's hand.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Boundless Realms

Search your library for up to X basic land cards, where X is the number of lands you control, put them onto the battlefield tapped, then shuffle.

Bane of Progress

When this creature enters, destroy all artifacts and enchantments. Put a +1/+1 counter on this creature for each permanent destroyed this way.

Omnath, Locus of Rage

Landfall — Whenever a land you control enters, create a 5/5 red and green Elemental creature token.
Whenever Omnath or another Elemental you control dies, Omnath deals 3 damage to any target.

Chandra's Incinerator

This spell costs {X} less to cast, where X is the total amount of noncombat damage dealt to your opponents this turn.
Trample
Whenever a source you control deals noncombat damage to an opponent, this creature deals that much damage to target creature or planeswalker that player controls.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Life's Legacy

As an additional cost to cast this spell, sacrifice a creature.
Draw cards equal to the sacrificed creature's power.

Rampaging Baloths

Trample
Landfall — Whenever a land you control enters, create a 4/4 green Beast creature token.

Ramunap Excavator

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Destructive Force

Each player sacrifices five lands of their choice. Destructive Force deals 5 damage to each creature.

Kodama's Reach

Misty Rainforest

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

Sylvan Scrying

Search your library for a land card, reveal it, put it into your hand, then shuffle.

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

Flamekin Harbinger

When this creature enters, you may search your library for an Elemental card, reveal it, then shuffle and put that card on top.

Ashaya, Soul of the Wild

Ashaya's power and toughness are each equal to the number of lands you control.
Nontoken creatures you control are Forest lands in addition to their other types. (They're still affected by summoning sickness.)

Harmonize

Tyrant of Discord

When this creature enters, target opponent chooses a permanent they control at random and sacrifices it. If a nonland permanent is sacrificed this way, repeat this process.

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.

Terramorphic Expanse

Sheltered Thicket

({T}: Add {R} or {G}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Titania, Nature's Force

You may play Forests from your graveyard.
Whenever a Forest you control enters, create a 5/3 green Elemental creature token.
Whenever an Elemental you control dies, you may mill three cards.

Molimo, Maro-Sorcerer

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Molimo's power and toughness are each equal to the number of lands you control.

Gruul Turf

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Nahiri's Lithoforming

Sacrifice X lands. For each land sacrificed this way, draw a card. You may play X additional lands this turn. Lands you control enter tapped this turn.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Wave of Vitriol

Each player sacrifices all artifacts, enchantments, and nonbasic lands they control. For each land sacrificed this way, its controller may search their library for a basic land card and put it onto the battlefield tapped. Then each player who searched their library this way shuffles.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

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}

Tempt with Vengeance

Tempting offer — Create X 1/1 red Elemental creature tokens with haste. Each opponent may create X 1/1 red Elemental creature tokens with haste. For each opponent who does, create X 1/1 red Elemental creature tokens with haste.