As long as X is in X's owner's opponent's hand, X's owner may cast X and activate X's abilities. That opponent can't cast X and plays with their hand revealed.
{U}{B}, {T}: Put X into target opponent's hand.
{3}{U}{B}: You may play a land or cast a spell from the hand X is in. If you cast a spell this way, you cast it without paying its mana cost.
Near Mint Foil - £0.30
Lightly Played Foil - £0.30
Moderately Played Foil - £0.20
Heavily Played Foil - £0.20
Damaged Foil - £0.10
Near Mint Foil Non English - £0.30
Lightly Played Foil Non English - £0.30
Moderately Played Foil Non English - £0.20
Heavily Played Foil Non English - £0.20
Damaged Foil Non English - £0.10