(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)
Underwater Tunnel
When you unlock this door, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Slimy Aquarium
When you unlock this door, manifest dread, then put a +1/+1 counter on that creature.
Near Mint - $0.10
Lightly Played - $0.10
Played - $0.10
Heavily Played - $0.10
Damaged - $0.10
Near Mint Non-English - $0.10
Lightly Played Non-English - $0.10
Played Non-English - $0.10
Heavily Played Non-English - $0.10
Damaged Non-English - $0.10
Foil Prices
Near Mint Foil - $0.10
Lightly Played Foil - $0.10
Played Foil - $0.10
Heavily Played Foil - $0.10
Damaged Foil - $0.10
Near Mint Foil Non-English - $0.10
Lightly Played Foil Non-English - $0.10
Played Foil Non-English - $0.10
Heavily Played Foil Non-English - $0.10
Damaged Foil Non-English - $0.10