Sagu Mauler

Morph lets you cast a card face down by paying 3 generic mana , and lets you turn the face-down permanent face up any time you have priority by paying its morph cost.

The face-down spell has no mana cost and has a mana value of 0. When you cast a face-down spell, put it on the stack face down so no other player knows what it is, and pay 3 generic mana . This is an alternative cost.

A permanent that turns face up or face down changes characteristics but is otherwise the same permanent. Spells and abilities that were targeting that permanent, as well as Auras and Equipment that were attached to the permanent, aren't affected.