Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Early Harvest

Target player untaps all basic lands they control.

Arbor Elf

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.

Vitalize

Explore

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

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Yedora, Grave Gardener

Whenever another nontoken creature you control dies, you may return it to the battlefield face down under its owner's control. It's a Forest land. (It has no other types or abilities.)

Jolrael, Empress of Beasts

{2}{G}, {T}, Discard two cards: All lands target player controls become 3/3 creatures until end of turn. They're still lands.

Blighted Woodland

{T}: Add {C}.
{3}{G}, {T}, Sacrifice Blighted Woodland: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Scute Swarm

Landfall — Whenever a land you control enters, create a 1/1 green Insect creature token. If you control six or more lands, create a token that's a copy of Scute Swarm instead.

Lotus Cobra

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

Gaea's Touch

{0}: You may put a basic Forest card from your hand onto the battlefield. Activate only as a sorcery and only once each turn.
Sacrifice Gaea's Touch: Add {G}{G}.

Darksteel Citadel

Earth Surge

Each land gets +2/+2 as long as it's a creature.

Sylvan Advocate

Vigilance
As long as you control six or more lands, Sylvan Advocate and land creatures you control get +2/+2.

Ezuri's Predation

For each creature your opponents control, create a 4/4 green Phyrexian Beast creature token. Each of those tokens fights a different one of those creatures.