2015-02-25 : Deathmist Raptor’s second ability triggers only if Deathmist Raptor is in the graveyard when a permanent you control is turned face up.

2015-02-25 : If a face-down creature with megamorph is turned face up some other way (for example, if you manifest a card with megamorph and then pay its mana cost to turn it face up), you won’t put a +1/+1 counter on it.

2015-02-25 : Megamorph is a variant of the morph ability. You can find more information on morph on cards with morph from the Khans of Tarkir set.

2015-02-25 : Turning a face-down creature with megamorph face up and putting a +1/+1 counter on it is a special action. It doesn’t use the stack and can’t be responded to.

2015-02-25 : You choose whether Deathmist Raptor will enter the battlefield face up or face down as the ability resolves. You may also choose to leave it in the graveyard.