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.

Armored Scrapgorger

Armored Scrapgorger gets +3/+0 as long as it has three or more oil counters on it.
{T}: Add one mana of any color.
Whenever Armored Scrapgorger becomes tapped, exile target card from a graveyard and put an oil counter on Armored Scrapgorger.

Buried in the Garden

Enchant land
When Buried in the Garden enters the battlefield, exile target nonland permanent you don't control until Buried in the Garden leaves the battlefield.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Jukai Preserver

When Jukai Preserver enters the battlefield, put a +1/+1 counter on target creature you control.
Channel — {2}{G}, Discard Jukai Preserver: Put a +1/+1 counter on each of up to two target creatures you control.

Thriving Grove

Thriving Grove enters the battlefield tapped.
As Thriving Grove enters the battlefield, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Sol Ring

Selesnya Guildgate

Selesnya Guildgate enters the battlefield tapped.
{T}: Add {G} or {W}.

Cankerbloom

{1}, Sacrifice Cankerbloom: Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Iron Apprentice

Iron Apprentice enters the battlefield with a +1/+1 counter on it.
When Iron Apprentice dies, if it had counters on it, put those counters on target creature you control.

Tail Swipe

Choose target creature you control and target creature you don't control. If you cast this spell during your main phase, the creature you control gets +1/+1 until end of turn. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Ironshell Beetle

When Ironshell Beetle enters the battlefield, put a +1/+1 counter on target creature.

Sandsteppe Mastodon

Reach
When Sandsteppe Mastodon enters the battlefield, bolster 5. (Choose a creature with the least toughness among creatures you control and put five +1/+1 counters on it.)

Journey to Nowhere

When Journey to Nowhere enters the battlefield, exile target creature.
When Journey to Nowhere leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Gryffwing Cavalry

Flying
Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
Whenever Gryffwing Cavalry attacks, you may pay {1}{W}. If you do, target attacking creature without flying gains flying until end of turn.

Hard-Hitting Question

Target creature you control deals damage equal to its power to target creature or planeswalker you don't control.

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

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.

Iron-Craw Crusher

Prototype {2}{G}{G} — 2/5 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Whenever Iron-Craw Crusher attacks, target attacking creature gets +X/+0 until end of turn, where X is Iron-Craw Crusher's power.

Tumbleweed Rising

Create an X/X green Elemental creature token, where X is the greatest power among creatures you control.
Plot {2}{G} (You may pay {2}{G} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Jadelight Spelunker

When Jadelight Spelunker enters the battlefield, it explores X times. (To have it explore, 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 that creature, then put the card back or put it into your graveyard.)

Commander's Sphere

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

Remnant of the Rising Star

Flying
Whenever another creature enters the battlefield under your control, you may pay {X}. When you do, put X +1/+1 counters on that creature.
As long as you control five or more modified creatures, Remnant of the Rising Star gets +5/+5 and has trample. (Equipment, Auras you control, and counters are modifications.)

Jugan Defends the Temple

(As this Saga enters and after your draw step, add a lore counter.)
I — Create a 1/1 green Human Monk creature token with "{T}: Add {G}."
II — Put a +1/+1 counter on each of up to two target creatures.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Jugan Defends the Temple // Remnant of the Rising Star

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.

Parish-Blade Trainee

Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
When Parish-Blade Trainee dies, put its counters on target creature you control.

Quirion Beastcaller

Whenever you cast a creature spell, put a +1/+1 counter on Quirion Beastcaller.
When Quirion Beastcaller dies, distribute X +1/+1 counters among any number of target creatures you control, where X is the number of +1/+1 counters on Quirion Beastcaller.

Bristly Bill, Spine Sower

Landfall — Whenever a land enters the battlefield under your control, put a +1/+1 counter on target creature.
{3}{G}{G}: Double the number of +1/+1 counters on each creature you control.

Promising Vein

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

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Staggering Size

Target creature gets +3/+3 and gains trample until end of turn.

Roaring Earth

Landfall — Whenever a land enters the battlefield under your control, put a +1/+1 counter on target creature or Vehicle you control.
Channel — {X}{G}{G}, Discard Roaring Earth: Put X +1/+1 counters on target land you control. It becomes a 0/0 green Spirit creature with haste. It's still a land.

Benevolent Hydra

Benevolent Hydra enters the battlefield with X +1/+1 counters on it.
If one or more +1/+1 counters would be put on another creature you control, that many plus one +1/+1 counters are put on it instead.
{T}, Remove a +1/+1 counter from Benevolent Hydra: Put a +1/+1 counter on another target creature you control.

Walking Skyscraper

This spell costs {1} less to cast for each modified creature you control. (Equipment, Auras you control, and counters are modifications.)
Trample
Walking Skyscraper has hexproof as long as it's untapped. (It can't be the target of spells or abilities your opponents control.)

Return to Nature

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Nature's Way

Target creature you control gains vigilance and trample until end of turn. It deals damage equal to its power to target creature you don't control.

Glint Weaver

Reach
When Glint Weaver enters the battlefield, distribute three +1/+1 counters among one, two, or three target creatures, then you gain life equal to the greatest toughness among creatures you control.

Final Showdown

Spree (Choose one or more additional costs.)
+ {1} — All creatures lose all abilities until end of turn.
+ {1} — Choose a creature you control. It gains indestructible until end of turn.
+ {3}{W}{W} — Destroy all creatures.

Vastwood Surge

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If this spell was kicked, put two +1/+1 counters on each creature you control.

Fertilid

Fertilid enters the battlefield with two +1/+1 counters on it.
{1}{G}, Remove a +1/+1 counter from Fertilid: Target player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Phantom Nantuko

Trample
Phantom Nantuko enters the battlefield with two +1/+1 counters on it.
If damage would be dealt to Phantom Nantuko, prevent that damage. Remove a +1/+1 counter from Phantom Nantuko.
{T}: Put a +1/+1 counter on Phantom Nantuko.

Lavaspur Boots

Equipped creature gets +1/+0 and has haste and ward {1}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
Equip {1}

Murasa Rootgrazer

Vigilance
{T}: You may put a basic land card from your hand onto the battlefield.
{T}: Return target basic land you control to its owner's hand.

Soul's Majesty

Draw cards equal to the power of target creature you control.

Hydra's Growth

Enchant creature
When Hydra's Growth enters the battlefield, put a +1/+1 counter on enchanted creature.
At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.

Invigorating Surge

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on that creature.

Tendril of the Mycotyrant

{5}{G}{G}: Put seven +1/+1 counters on target noncreature land you control. It becomes a 0/0 Fungus creature with haste. It's still a land.

Knight of Glory

Protection from black (This creature can't be blocked, targeted, dealt damage, or enchanted by anything black.)
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)

Joraga Invocation

Each creature you control gets +3/+3 until end of turn and must be blocked this turn if able.

Flowering of the White Tree

Legendary creatures you control get +2/+1 and have ward {1}.
Nonlegendary creatures you control get +1/+1.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Plains

Mana Tithe

Counter target spell unless its controller pays {1}.

Briarpack Alpha

Flash (You may cast this spell any time you could cast an instant.)
When Briarpack Alpha enters the battlefield, target creature gets +2/+2 until end of turn.

Command Tower

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

Dragon Bell Monk

Vigilance
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Arcane Signet

Utopia Sprawl

Enchant Forest
As Utopia Sprawl enters the battlefield, choose a color.
Whenever enchanted Forest is tapped for mana, its controller adds an additional one mana of the chosen color.

Reprieve

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

Experiment One

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Remove two +1/+1 counters from Experiment One: Regenerate Experiment One. (The next time this creature would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

Blossoming Defense

Target creature you control gets +2/+2 and gains hexproof until end of turn.

Drover Grizzly

Whenever Drover Grizzly attacks while saddled, creatures you control gain trample until end of turn.
Saddle 1 (Tap any number of other creatures you control with total power 1 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Join Forces

Untap up to two target creatures. They each get +2/+2 until end of turn.

Drifting Meadow

Drifting Meadow enters the battlefield tapped.
{T}: Add {W}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Sheriff of Safe Passage

Sheriff of Safe Passage enters the battlefield with a +1/+1 counter on it plus an additional +1/+1 counter on it for each other creature you control.
Plot {1}{W} (You may pay {1}{W} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Soul's Might

Put X +1/+1 counters on target creature, where X is that creature's power.

Sovereign Okinec Ahau

Ward {2}
Whenever Sovereign Okinec Ahau attacks, for each creature you control with power greater than that creature's base power, put a number of +1/+1 counters on that creature equal to the difference.

Valorous Stance

Choose one —
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
• Destroy target creature with toughness 4 or greater.

Conduit Pylons

When Conduit Pylons enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Armored Armadillo

Ward {1} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
{3}{W}: Armored Armadillo gets +X/+0 until end of turn, where X is its toughness.

Adaptive Sporesinger

Vigilance
When Adaptive Sporesinger enters the battlefield, choose one —
• Target creature gets +2/+2 and gains vigilance until end of turn.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)