Morph
This ability is written Morph (cost). A card with morph may be cast face-down by paying 3 colorless mana. While face-down, the creature is a colorless, nameless and typeless 2/2 creature. At any time, a player may pay the creature's morph cost and turn the creature face-up. Many cards with morph have additional abilities when they are turned face-up. Morph was introduced in the Onslaught block.
Only creatures with morph may be played face-down. If a card without morph is turned face down by an effect, it can't be turned face up, because it has no morph ability with which to do so. At the end of the game, or whenever a face down creature would leave the battlefield, it is revealed to all players. In addition to providing information to players, this ensures that players don't cheat by playing cards without morph face-down.
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