The Gitrog Monster

Deathtouch
At the beginning of your upkeep, sacrifice The Gitrog Monster unless you sacrifice a land.
You may play an additional land on each of your turns.
Whenever one or more land cards are put into your graveyard from anywhere, draw a card.

Constant Mists

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.)
Prevent all combat damage that would be dealt this turn.

City of Traitors

When you play another land, sacrifice City of Traitors.
{T}: Add {C}{C}.

Burning Sands

Whenever a creature dies, that creature's controller sacrifices a land.

Army Ants

{T}, Sacrifice a land: Destroy target land.

Lotus Vale

If Lotus Vale would enter the battlefield, sacrifice two untapped lands instead. If you do, put Lotus Vale onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add three mana of any one color.

Aura Fracture

Sacrifice a land: Destroy target enchantment.

Knight of the Reliquary

Knight of the Reliquary gets +1/+1 for each land card in your graveyard.
{T}, Sacrifice a Forest or Plains: Search your library for a land card, put it onto the battlefield, then shuffle.

Garth One-Eye

{T}: Choose a card name that hasn't been chosen from among Disenchant, Braingeyser, Terror, Shivan Dragon, Regrowth, and Black Lotus. Create a copy of the card with the chosen name. You may cast the copy. (You still pay its costs.)

Damping Engine

A player who controls more permanents than each other player can't play lands or cast artifact, creature, or enchantment spells. That player may sacrifice a permanent for that player to ignore this effect until end of turn.

Expedition Map

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

Natural Balance

Each player who controls six or more lands chooses five lands they control and sacrifices the rest. Each player who controls four or fewer lands may search their library for up to X basic land cards and put them onto the battlefield, where X is five minus the number of lands they control. Then each player who searched their library this way shuffles.

Lotus Cobra

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

Destructive Flow

At the beginning of each player's upkeep, that player sacrifices a nonbasic land.

Magus of the Balance

{4}{W}, {T}, Sacrifice Magus of the Balance: Each player chooses a number of lands they control equal to the number of lands controlled by the player who controls the fewest, then sacrifices the rest. Players discard cards and sacrifice creatures the same way.

Epicenter

Target player sacrifices a land.
Threshold — Each player sacrifices all lands they control instead if seven or more cards are in your graveyard.

Dredge

Sacrifice a creature or land.
Draw a card.

Earthlink

At the beginning of your upkeep, sacrifice Earthlink unless you pay {2}.
Whenever a creature dies, that creature's controller sacrifices a land.

Destructive Urge

Enchant creature
Whenever enchanted creature deals combat damage to a player, that player sacrifices a land.

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.

Restore Balance

Suspend 6—{W}
Each player chooses a number of lands they control equal to the number of lands controlled by the player who controls the fewest, then sacrifices the rest. Players sacrifice creatures and discard cards the same way.

Goblin Trenches

{2}, Sacrifice a land: Create two 1/1 red and white Goblin Soldier creature tokens.

Destructive Force

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

Lotus Field

Hexproof
Lotus Field enters the battlefield tapped.
When Lotus Field enters the battlefield, sacrifice two lands.
{T}: Add three mana of any one color.