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.

Aftermath Analyst

When Aftermath Analyst enters the battlefield, mill three cards.
{3}{G}, Sacrifice Aftermath Analyst: Return all land cards from your graveyard to the battlefield tapped.

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.

Undergrowth Recon

At the beginning of your upkeep, return target land card from your graveyard to the battlefield tapped.

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.

Wayward Swordtooth

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
You may play an additional land on each of your turns.
Wayward Swordtooth can't attack or block unless you have the city's blessing.

Azusa, Lost but Seeking

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

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 the battlefield tapped this turn.

Elvish Reclaimer

Elvish Reclaimer 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.

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.

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.

Generous Gift

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

Sprouting Goblin

Kicker {G} (You may pay an additional {G} as you cast this spell.)
When Sprouting Goblin enters the battlefield, if it was kicked, search your library for a land card with a basic land type, reveal it, put it into your hand, then shuffle.
{R}, {T}, Sacrifice a land: Draw a card.

Worldsoul's Rage

Worldsoul's Rage deals X damage to any target. Put up to X land cards from your hand and/or graveyard onto the battlefield tapped.

Lotus Cobra

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

Garruk's Uprising

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.)
Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

Splendid Reclamation

Return all land cards from your graveyard to the battlefield tapped.

Zuran Orb

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.

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.