Excavating Anurid

When Excavating Anurid enters, you may sacrifice a land. If you do, draw a card.
Threshold — As long as seven or more cards are in your graveyard, Excavating Anurid gets +1/+1 and has vigilance.

Scythe Tiger

Shroud (This creature can't be the target of spells or abilities.)
When Scythe Tiger enters, sacrifice it unless you sacrifice a land.

Springbloom Druid

When this creature enters, you may sacrifice a land. If you do, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Harvest Wurm

When Harvest Wurm enters, sacrifice it unless you return a basic land card from your graveyard to your hand.

Murasa Behemoth

Trample
Murasa Behemoth gets +3/+3 as long as there is a land card in your graveyard.