Cards that go away on their own, like dim shield, virus, and sundial should not be effected by this card. It should be only cards that are destroyed through an effect (PC including butterfly effect, and CC damage and poison).
I suppose rewind gets partially countered by this card, and puts the card in the enemy's hand instead of on top of his deck. So this card doesn't work well with time's most potent CC. I suppose that is ok.
It has synergy with all soft CC (bb, antimatter, lobo, freeze, sundial, dim shield, turtle shield, etc).
I assume that if you deflag this card, it does not go back to your hand... unless there are two in play.
It might be interesting to make this card be a shield, although it might make it unplayable.