You wouldn’t expect a captivating and heavily story-oriented game like BioShock: Infinite to have sidequests, but it actually does.
Sure, they aren’t as long and tedious as the ones you’d find in classy RPG games like the Elder Scrolls or Final Fantasy, but they serve as a good (but mostly short-lived) breaks from the main storyline. And of course, they always end up pointing to a nice little reward for you to collect.
There are a total of six optional missions in BioShock: Infinite. Two of them get you access to chests, while the rest point to code books and voxophones.
BioShock Infinite Side Quests Vox Codes and Chests
Comstock Center Rooftops
Locked Chest #1 – The first of the two locked chests are in the Lansdowne Residence, in the bedroom. In order to unlock the chest, you’ll need to search for a key in the Fraternal Order of the Raven.
Locked Chest #2 – The main alter of the Fraternal Order Chapel has a bottle of infusion, with which is the key (a book also lays next to it). Take this key back to the Lansdowne Residence, and you can unlock the chest for another bottle of infusion.
Hall of Heroes
Vox Code #1 – There’s a building with a cannon monument in the Soldier’s Field. In the muzzle of that cannon is a Code Book. Grab the book and take it to the Fellow Traveler restaurant. There is a secret message written scribbled in blood in there. Interact with it, and then use the hat hanging on the hook to enter the secret room.
Plaza of Zeal
Vox Code #2 – Another Code Book can be found at the Good Time Club. Inside the club’s boiler room are a couple of boxes, which have the book on top. There’s a clock on the right side of the wall, which acts as the access to the secret room. Don’t worry about the items collected, as you’ll know about them later on.
Bull Yard Impound
Locked Chest #3 – In the Bull Yard Impound is a chest, whose key is actually located in the Graveyard Shift’s basement. If you missed it, then consider taking the sky rail outside to the Graveyard Shift bar and obtaining it.
Secret Room of Salty Oyster
There is a secret room in the Salty Oyster restaurant (Port Prosperity), but before you can access it you have to locate the Founder’s Bookstore after the Grand Central Depot. There’s a bridge patrolled by snipers past the Grand Central Depot. Underneath the bridge is a doorway to the Founder’s Bookstore.
You’ll need one lockpick to open the locked door there. Acquire the voxophone, and then go back to the Salty Oyster and use the button under the cash register to open the secret room.
Bank of the Prophet
Vox Code #3 – In Downtown Emporia, there is a Hudson’s clothing store with a gate that bars half the tunnel. Go inside and grab the code book from the basement. Now, you’ll just need to carry it with yourself till you enter the Bank of the Prophet.
When you’re in the bank vaults, there is a room with blood scribbles of HOARDER just before encountering a bunch of snipers. The switch for the secret room there is the typewriter.