Twist Reality

At any time, you can look at a face-down spell or permanent you control. You can't look at face-down permanents or spells you don't control unless an effect instructs or allows you to do so.

You must ensure that your face-down spells and permanents can be easily differentiated from each other. You're not allowed to mix up the cards that represent them on the battlefield to confuse other players. The order in which they entered should remain clear, as well as what ability caused them to be face down. (This includes manifest, disguise, cloak, morph, and a few older effects that turn cards face down.) Common methods for doing this include using markers or dice, or simply placing them in order on the battlefield.

If a face-down creature loses its abilities, it can't be turned face up with a disguise or morph ability because it will no longer have that ability (or the associated cost) once face up.