Once Porter has The Thinker’s machine code in hand, he plans to use a bathysphere to escape Rapture. Unfortunately, Lamb’s torpedoes shoot down any bathysphere attempting to leave the city. Porter needs you to find a bathysphere signal beacon that can be hacked and turned into a signal jammer, thwarting Lamb’s defenses.
Airlock
Descend the stairs beyond the lobby and ready yourself with Electro Bolt and the Ion Laser. Ignore the Houdini Splicer that attacks and focus on her two Security Bots instead. Zap them out of the sky and hack them to turn them against her. Purchase a Gene Tonic Slot from the Gatherer’s Garden, then proceed through the door toward the airlock area.
Locate the Upgraded Shotgun and Audio Diary (“The Man and the Machine”) beyond the door. The Upgraded Shotgun increases the Shotgun’s capacity from two to six shells. Hack the Security Camera beyond the curtain of water and proceed down the stairs to the pool of electrocuted water where a Splicer stuck his finger in the socket. Throw the Gravity Well at the Splicer to break the circuit and open the door. Pick up the Audio Diary (“Signal Beacon”).
Throw the lever in the airlock and step outside. There are three ADAM Slugs in this area. The first is to the right, near the window. The second is on a boulder to the left, where the trail splits, and the third is on the rocks near the pink glowing coral opposite the bathysphere. The signal beacon you seek is at the end of the path, on the outside of a bathysphere.
