Rogue Elephant

When Rogue Elephant enters, sacrifice it unless you sacrifice a Forest.

Krosan Wayfarer

Sacrifice Krosan Wayfarer: You may put a land card from your hand onto the battlefield.

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.

Have

Winding Way

Choose creature or land. Reveal the top four cards of your library. Put all cards of the chosen type revealed this way into your hand and the rest into your graveyard.

Harvest Wurm

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