Mountain

Spelunking

When Spelunking enters, 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 untapped.

Scythe Leopard

Landfall — Whenever a land you control enters, Scythe Leopard gets +1/+1 until end of turn.

Despair

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Until end of turn, creatures you control gain menace and "Whenever this creature deals combat damage to a player, that player discards a card."

Driven

Until end of turn, creatures you control gain trample and "Whenever this creature deals combat damage to a player, draw a card."

Driven // Despair

Explore

You may play an additional land this turn.
Draw a card.

Scale the Heights

Put a +1/+1 counter on up to one target creature. You gain 2 life. You may play an additional land this turn.
Draw a card.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Escape Tunnel

{T}, Sacrifice Escape Tunnel: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
{T}, Sacrifice Escape Tunnel: Target creature with power 2 or less can't be blocked this turn.

Jaddi Offshoot

Defender
Landfall — Whenever a land you control enters, you gain 1 life.

Arboreal Grazer

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

Forest

Cabaretti Courtyard

When Cabaretti Courtyard enters, sacrifice it. When you do, search your library for a basic Mountain, Forest, or Plains card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Makindi Sliderunner

Trample
Landfall — Whenever a land you control enters, Makindi Sliderunner gets +1/+1 until end of turn.

Akoum Hellhound

Landfall — Whenever a land you control enters, Akoum Hellhound gets +2/+2 until end of turn.

Plated Geopede

First strike
Landfall — Whenever a land you control enters, Plated Geopede gets +2/+2 until end of turn.

Brushfire Elemental

Haste
Brushfire Elemental can't be blocked by creatures with power 2 or less.
Landfall — Whenever a land you control enters, Brushfire Elemental gets +2/+2 until end of turn.