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.

Oracle of Mul Daya

You may play an additional land on each of your turns.
Play with the top card of your library revealed.
You may play lands from the top of your library.

Phylath, World Sculptor

When Phylath, World Sculptor enters, create a 0/1 green Plant creature token for each basic land you control.
Landfall — Whenever a land you control enters, put four +1/+1 counters on target Plant you control.

Traverse the Outlands

Search your library for up to X basic land cards, where X is the greatest power among creatures you control. Put those cards onto the battlefield tapped, then shuffle.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Explore

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

Wrenn and Seven

+1: Reveal the top four cards of your library. Put all land cards revealed this way into your hand and the rest into your graveyard.
0: Put any number of land cards from your hand onto the battlefield tapped.
−3: Create a green Treefolk creature token with reach and "This creature's power and toughness are each equal to the number of lands you control."
−8: Return all permanent cards from your graveyard to your hand. You get an emblem with "You have no maximum hand size."

Into the North

Search your library for a snow land card, put it onto the battlefield tapped, then shuffle.

Mountain

Perilous Forays

{1}, Sacrifice a creature: Search your library for a land card with a basic land type, put it onto the battlefield tapped, then shuffle.

Instruments of War

Flash
As Instruments of War enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.

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.

Animist's Awakening

Reveal the top X cards of your library. Put all land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap those lands.

Gut, True Soul Zealot

Whenever you attack, you may sacrifice another creature or an artifact. If you do, create a 4/1 black Skeleton creature token with menace that's tapped and attacking. (It can't be blocked except by two or more creatures.)
Choose a Background (You can have a Background as a second commander.)