You may choose not to untap Amber Prison during your untap step. {4}, {T}: Tap target artifact, creature, or land. That permanent doesn't untap during its controller's untap step for as long as Amber Prison remains tapped.
Near Mint - $0.20
Lightly Played - $0.20
Moderately Played - $0.20
Heavily Played - $0.10
Damaged - $0.10
Near Mint Spanish - $0.20
Lightly Played Spanish - $0.20
Moderately Played Spanish - $0.20
Heavily Played Spanish - $0.10
Damaged Spanish - $0.10