Oracle Text

Target creature you control gains protection from creatures your opponents control until end of turn. Untap it.

Card Rulings

2/1/2014 Abilities of creature cards not on the battlefield owned by an opponent can’t target that creature, and damage those cards would deal to the creature is prevented.
2/1/2014 If another player gains control of the creature after Crypsis resolves, the creature will have protection from creatures controlled by opponents of its new controller.