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.

Lush Portico

({T}: Add {G} or {W}.)
Lush Portico enters the battlefield tapped.
When Lush Portico enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Emeria Shepherd

Flying
Landfall — Whenever a land enters the battlefield under your control, you may return target nonland permanent card from your graveyard to your hand. If that land is a Plains, you may return that nonland permanent card to the battlefield instead.

Nylea, Keen-Eyed

Indestructible
As long as your devotion to green is less than five, Nylea isn't a creature.
Creature spells you cast cost {1} less to cast.
{2}{G}: Reveal the top card of your library. If it's a creature card, put it into your hand. Otherwise, you may put it into your graveyard.

Mentor of the Meek

Whenever another creature with power 2 or less enters the battlefield under your control, you may pay {1}. If you do, draw a card.

Field of the Dead

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

Gwenna, Eyes of Gaea

{T}: Add two mana in any combination of colors. Spend this mana only to cast creature spells or activate abilities of a creature or creature card.
Whenever you cast a creature spell with power 5 or greater, put a +1/+1 counter on Gwenna, Eyes of Gaea and untap it.

The Great Henge

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
{T}: Add {G}{G}. You gain 2 life.
Whenever a nontoken creature enters the battlefield under your control, put a +1/+1 counter on it and draw a card.

Joraga Treespeaker

Level up {1}{G} ({1}{G}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-4
1/2
{T}: Add {G}{G}.
LEVEL 5+
1/4
Elves you control have "{T}: Add {G}{G}."

Cavern of Souls

As Cavern of Souls enters the battlefield, 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, and that spell can't be countered.

Emeria, the Sky Ruin

Emeria, the Sky Ruin enters the battlefield tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

Gigantomancer

{1}: Target creature you control has base power and toughness 7/7 until end of turn.

Savage Summoning

This spell can't be countered.
The next creature spell you cast this turn can be cast as though it had flash. That spell can't be countered. That creature enters the battlefield with an additional +1/+1 counter on it.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Priest of Titania

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

Mangara of Corondor

{T}: Exile Mangara of Corondor and target permanent.

Command Tower

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

Dryad Arbor

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

Thraben Inspector

When Thraben Inspector enters the battlefield, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Knight-Errant of Eos

Convoke
When Knight-Errant of Eos enters the battlefield, look at the top six cards of your library. You may reveal up to two creature cards with mana value X or less from among them, where X is the number of creatures that convoked Knight-Errant of Eos. Put the revealed cards into your hand, then shuffle.

Tiller Engine

Whenever a land enters the battlefield tapped and under your control, choose one —
• Untap that land.
• Tap target nonland permanent an opponent controls.

Vizier of the Menagerie

You may look at the top card of your library any time.
You may cast creature spells from the top of your library.
You can spend mana of any type to cast creature spells.

Guardian of Faith

Flash
Vigilance
When Guardian of Faith enters the battlefield, any number of other target creatures you control phase out. (Treat them and anything attached to them as though they don't exist until their controller's next turn.)

Augur of Autumn

You may look at the top card of your library any time.
You may play lands from the top of your library.
Coven — As long as you control three or more creatures with different powers, you may cast creature spells from the top of your library.

Arctic Treeline

({T}: Add {G} or {W}.)
Arctic Treeline enters the battlefield tapped.

Devoted Druid

{T}: Add {G}.
Put a -1/-1 counter on Devoted Druid: Untap Devoted Druid.

Soul of the Harvest

Trample
Whenever another nontoken creature enters the battlefield under your control, you may draw a card.

Guardian Project

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Beast Within

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

Novice Inspector

When Novice Inspector enters the battlefield, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Fyndhorn Elves

Radiant Grove

({T}: Add {G} or {W}.)
Radiant Grove enters the battlefield tapped.

Welcoming Vampire

Flying
Whenever one or more other creatures with power 2 or less enter the battlefield under your control, draw a card. This ability triggers only once each turn.

Jazal Goldmane

First strike
{3}{W}{W}: Attacking creatures you control get +X/+X until end of turn, where X is the number of attacking creatures.

Dauntless Escort

Sacrifice Dauntless Escort: Creatures you control gain indestructible until end of turn.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Spirited Companion

When Spirited Companion enters the battlefield, draw a card.

Savannah

Forest

Whitemane Lion

Flash
When Whitemane Lion enters the battlefield, return a creature you control to its owner's hand.

Spelunking

When Spelunking enters the battlefield, draw a card, then you may put a land card from your hand onto the battlefield. If you put a Cave onto the battlefield this way, you gain 4 life.
Lands you control enter the battlefield untapped.

Elvish Visionary

When Elvish Visionary enters the battlefield, draw a card.

Scattered Groves

({T}: Add {G} or {W}.)
Scattered Groves enters the battlefield tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Clever Concealment

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Any number of target nonland permanents you control phase out. (Treat them and anything attached to them as though they don't exist until your next turn.)

Birds of Paradise

Kamahl, Fist of Krosa

{G}: Target land becomes a 1/1 creature until end of turn. It's still a land.
{2}{G}{G}{G}: Creatures you control get +3/+3 and gain trample until end of turn.

Kor Skyfisher

Flying
When Kor Skyfisher enters the battlefield, return a permanent you control to its owner's hand.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Shaman of Forgotten Ways

{T}: Add two mana in any combination of colors. Spend this mana only to cast creature spells.
Formidable — {9}{G}{G}, {T}: Each player's life total becomes the number of creatures they control. Activate only if creatures you control have total power 8 or greater.

Tireless Provisioner

Landfall — Whenever a land enters the battlefield under your control, create a Food token or a Treasure token. (Food is an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life." Treasure is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Canopy Vista

({T}: Add {G} or {W}.)
Canopy Vista enters the battlefield tapped unless you control two or more basic lands.

Snow-Covered Forest

Nissa, Resurgent Animist

Landfall — Whenever a land enters the battlefield under your control, add one mana of any color. Then if this is the second time this ability has resolved this turn, reveal cards from the top of your library until you reveal an Elf or Elemental card. Put that card into your hand and the rest on the bottom of your library in a random order.

Elephant

Karametra, God of Harvests

Indestructible
As long as your devotion to green and white is less than seven, Karametra isn't a creature.
Whenever you cast a creature spell, you may search your library for a Forest or Plains card, put it onto the battlefield tapped, then shuffle.

Lapse of Certainty

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Treasure

{T}, Sacrifice this artifact: Add one mana of any color.

Llanowar Elves

Temple Garden

({T}: Add {G} or {W}.)
As Temple Garden enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Reprieve

Return target spell to its owner's hand.
Draw a card.

Boreal Druid

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.

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Tireless Tracker

Landfall — Whenever a land enters the battlefield under your control, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice a Clue, put a +1/+1 counter on Tireless Tracker.

Bountiful Promenade

Bountiful Promenade enters the battlefield tapped unless you have two or more opponents.
{T}: Add {G} or {W}.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Delighted Halfling

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell, and that spell can't be countered.

Arbor Elf

Generous Gift

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

Veil of Summer

Draw a card if an opponent has cast a blue or black spell this turn. Spells you control can't be countered this turn. You and permanents you control gain hexproof from blue and from black until end of turn. (You and they can't be the targets of blue or black spells or abilities your opponents control.)

Glorious Protector

Flash
Flying
When Glorious Protector enters the battlefield, you may exile any number of non-Angel creatures you control until Glorious Protector leaves the battlefield.
Foretell {2}{W}

Glimpse of Nature

Whenever you cast a creature spell this turn, draw a card.

Primordial Sage

Whenever you cast a creature spell, you may draw a card.

Rite of Harmony

Whenever a creature or enchantment enters the battlefield under your control this turn, draw a card.
Flashback {2}{G}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Food

{2}, {T}, Sacrifice this artifact: You gain 3 life.

Elvish Mystic

Lotus Cobra

Landfall — Whenever a land enters the battlefield under your control, add one mana of any color.

Zendikar Resurgent

Whenever you tap a land for mana, add one mana of any type that land produced. (The types of mana are white, blue, black, red, green, and colorless.)
Whenever you cast a creature spell, draw a card.

Elven Chorus

You may look at the top card of your library any time.
You may cast creature spells from the top of your library.
Creatures you control have "{T}: Add one mana of any color."

Plains

Luminous Broodmoth

Flying
Whenever a creature you control without flying dies, return it to the battlefield under its owner's control with a flying counter on it.

Beast

Skyclave Apparition

When Skyclave Apparition enters the battlefield, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less.
When Skyclave Apparition leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

Clue

{2}, Sacrifice this artifact: Draw a card.

Amulet of Vigor

Whenever a permanent enters the battlefield tapped and under your control, untap it.

Zombie

Silverback Elder

Whenever you cast a creature spell, choose one —
• Destroy target artifact or enchantment.
• Look at the top five cards of your library. You may put a land card from among them onto the battlefield tapped. Put the rest on the bottom of your library in a random order.
• You gain 4 life.

Illusion

Snow-Covered Plains

Itlimoc, Cradle of the Sun

(Transforms from Growing Rites of Itlimoc.)
{T}: Add {G}.
{T}: Add {G} for each creature you control.

Growing Rites of Itlimoc

When Growing Rites of Itlimoc enters the battlefield, look at the top four cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.
At the beginning of your end step, if you control four or more creatures, transform Growing Rites of Itlimoc.

Growing Rites of Itlimoc // Itlimoc, Cradle of the Sun

Gaea's Cradle

{T}: Add {G} for each creature you control.

Eternal Witness

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