When Grave Burrows enters the battlefield, return a land you control to its owner's hand.
: Add or to your mana pool.
Put Grave Burrows on top of your library: Add to your mana pool.
: Return Grave Burrows to its owner's hand.
: Add 
or 
to your mana pool.
to your mana pool. : Return Grave Burrows to its owner's hand.
