Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters the battlefield tapped.
Whenever a Mountain enters the battlefield under your control, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Dark Confidant

At the beginning of your upkeep, reveal the top card of your library and put that card into your hand. You lose life equal to its mana value.

Barren Moor

Barren Moor enters the battlefield tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Nurturing Peatland

{T}, Pay 1 life: Add {B} or {G}.
{1}, {T}, Sacrifice Nurturing Peatland: Draw a card.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Eternal Witness

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

Life from the Loam

Return up to three target land cards from your graveyard to your hand.
Dredge 3 (If you would draw a card, you may mill three cards instead. If you do, return this card from your graveyard to your hand.)

Arboreal Grazer

Reach
When Arboreal Grazer enters the battlefield, you may put a land card from your hand onto the battlefield tapped.

Abrupt Decay

This spell can't be countered.
Destroy target nonland permanent with mana value 3 or less.

Forest

Snow-Covered Swamp

Treetop Village

Treetop Village enters the battlefield tapped.
{T}: Add {G}.
{1}{G}: Treetop Village becomes a 3/3 green Ape creature with trample until end of turn. It's still a land. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Ghost Quarter

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

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.

Snow-Covered Forest

Overgrown Tomb

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

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.

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.

Verdant Catacombs

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

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Seasons Past

Return any number of cards with different mana values from your graveyard to your hand. Put Seasons Past on the bottom of its owner's library.

Urborg, Tomb of Yawgmoth

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

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Windswept Heath

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

Inquisition of Kozilek

Target player reveals their hand. You choose a nonland card from it with mana value 3 or less. That player discards that card.

Maelstrom Pulse

Destroy target nonland permanent and all other permanents with the same name as that permanent.

Tranquil Thicket

Tranquil Thicket enters the battlefield tapped.
{T}: Add {G}.
Cycling {G} ({G}, Discard this card: Draw a card.)

Swamp

Courser of Kruphix

Play with the top card of your library revealed.
You may play lands from the top of your library.
Landfall — Whenever a land enters the battlefield under your control, you gain 1 life.

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Damnation

Destroy all creatures. They can't be regenerated.

Mortuary Mire

Mortuary Mire enters the battlefield tapped.
When Mortuary Mire enters the battlefield, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Liliana of the Veil

+1: Each player discards a card.
−2: Target player sacrifices a creature.
−6: Separate all permanents target player controls into two piles. That player sacrifices all permanents in the pile of their choice.