Luna, Royal Moonlight

Flash. Flying. Indestructible.
Other permanents you control have hexproof.
At the beginning of combat, you may look at
the top three cards of your library. You may
choose one artifact or enchantment, reveal it,
and put it onto the battlefield under your
control with a dream counter. Put any
remaining cards into your graveyard. Then,
if you control at least three permanents with
dream counters, transform Luna, Royal
Moonlight.