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.

Aesi, Tyrant of Gyre Strait

You may play an additional land on each of your turns.
Landfall — Whenever a land you control enters, you may draw a card.

Azusa, Lost but Seeking

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

Veil of Summer

Draw a card if an opponent has cast a blue or black spell this turn. Spells you control can't be countered this turn. You and permanents you control gain hexproof from blue and from black until end of turn. (You and they can't be the targets of blue or black spells or abilities your opponents control.)

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Slogurk, the Overslime

Trample
Whenever a land card is put into your graveyard from anywhere, put a +1/+1 counter on Slogurk, the Overslime.
Remove three +1/+1 counters from Slogurk: Return it to its owner's hand.
When Slogurk leaves the battlefield, return up to three target land cards from your graveyard to your hand.

Augur of Autumn

You may look at the top card of your library any time.
You may play lands from the top of your library.
Coven — As long as you control three or more creatures with different powers, you may cast creature spells from the top of your library.

Druid Class

(Gain the next level as a sorcery to add its ability.)
Landfall — Whenever a land you control enters, you gain 1 life.
{2}{G}: Level 2
You may play an additional land on each of your turns.
{4}{G}: Level 3
When this Class becomes level 3, target land you control becomes a creature with haste and "This creature's power and toughness are each equal to the number of lands you control." It's still a land.

Sylvan Safekeeper

Sacrifice a land: Target creature you control gains shroud until end of turn. (It can't be the target of spells or abilities.)

Walk the Aeons

Buyback—Sacrifice three Islands. (You may sacrifice three Islands in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Target player takes an extra turn after this one.

Counterspell

Llanowar Elves

World Shaper

Whenever World Shaper attacks, you may mill three cards.
When World Shaper dies, return all land cards from your graveyard to the battlefield tapped.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Eternal Witness

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

Crucible of Worlds

Sol Ring

Exploration

You may play an additional land on each of your turns.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.