When Treetop Barrens enters the battlefield, sacrifice it unless you pay .
: Add to your mana pool.
: Add or to your mana pool. Each opponent gains 1 life.
: Regenerate Treetop Barrens.
.
: Add 
to your mana pool.: Add or 
to your mana pool. Each opponent gains 1 life.: Regenerate Treetop Barrens.
