When Misty Bosk enters the battlefield, sacrifice it unless you pay .
: Add or to your mana pool.
Put Misty Bosk on top of your library: Add to your mana pool.
: Misty Bosk becomes a 2/2 black Horror creature until end of turn. It's still a land.
.
: Add or 
to your mana pool.
to your mana pool. 
: Misty Bosk becomes a 2/2 black Horror creature until end of turn. It's still a land.
