A mag-locked door is cutting you off from Operations. The Gravity Well Plasmid would be useful in disabling the resistors that keep the magnetic lock from overloading. Search Minerva’s Den for the Gravity Well Plasmid.
Air-Tite Archives
Zap the door control with Electro Bolt to enter the Air-Tite Archives area. Hack the Security Camera in the entryway to Air-Tite Archives and collect the Audio Diary (“The Wager”) from the chair on the left. Hack-and-smash the Health Stations in the restrooms to come away with four free First-Aid Kits and continue on to the reception area.
Collect the Ion Laser Intensity Upgrade from the dead Lancer on the stairs. This upgrade increases the damage dealt by the Ion Laser. Two Leadhead Splicers attack just beyond the dead Lancer. Draw them and their Security Bots back toward the Security Camera and either use the Bot Shutdown panel to deactivate the Security Bots that come or use Electro Bolt on the Splicers’ Security Bots and hack those. Either way, try to get yourself a pair of Security Bots here.
Ascend the stairs to New Accounts, hack the Turret near the door, and head inside to find the fourth Vacuum Bot and the Booze Hound tonic. Return the way you came and ascend the stairs near the Gene Bank to find another Audio Diary (“Prying Eyes”). Continue west around the counter and descend the stairs on the left to the water-filled lower level. Here you can find another Audio Diary (“A Possible Solution”) and the Shotgun. Use the Hack Tool to open the locked door, via the panel beyond the hole in the wall, to locate the weapon.
Return to the main level and continue straight ahead to the Warehouse section of the Air-Tite Archives. The door directly ahead is locked, so descend the stairs on the right, grab the Audio Diary (“Thinker Input 1”) and use the Hack Tool to fire a Remote Hack Dart through the hole in the ceiling to hack the door control in the locked room. Hack the Safe around the corner in this lower area to obtain 50 Dollars, 18 Trap Rivets, and two Mini-Turrets.
Befriend one of the Spider Splicers and descend the stairs toward the Circus of Values. Use the Hack Tool to hack the Rocket Turret before it is destroyed by your Security Bots, then repair it. It will come in handy on the return trip. Scavenge the empty shelves for an Auto-Hack Tool and Burst Cells, then proceed north to the room left of the Rocket Turret where you’ll find the Natural Camouflage tonic and a Turret in the water. Hit the water with Electro Bolt to destroy the Turret and grab the tonic.
Note the Plasmid on the ledge high above the Health Station near the Operations Manager’s Office—this is the Plasmid you’ll need to break the lock off the door to Operations. Ascend the stairs to the right and go through the door to collect the Gravity Well Plasmid and an Audio Diary (“Implicating Porter”). There’s also a Safe containing 50 Dollars, 18 Trap Rivets, and 100 Burst Cells in the office. Purchase some Rocket Spear Ammo from the vending machine on your way back through the Warehouse. Now that you have the Gravity Well, you can make your way to Operations, but it is recommended that you take some time to deal with the final Little Sister, the ADAM Gathers, and to seek out the remaining Vacuum Bot.
Little Sister Encounter
You’re likely to encounter the third Little Sister and her Lancer Big Daddy on your way out of the Warehouse. Lure the Big Daddy down the stairs toward the Circus of Values machine and the Rocket Turret that you hacked earlier (near the empty canister shelves). Hit the Lancer with your Rocket Spears and Thermal Cells. Resist the temptation to hurl your new Gravity Well Plasmid at the Lancer because it may inadvertently destroy your Security Bots. Instead, continue to zap it with Electro Bolt while it’s busy defending itself against your mechanical allies. Charge up a Burst Cell attack with the Ion Laser to finish it off.
Gather #1: WAREHOUSE
The first Gather Corpse for this Little Sister is right at the base of the stairs in the Warehouse, in direct view of the Rocket Turret. Put a ring of Trap Rivets around the Little Sister, equip Hypnotize 2 and your Shotgun, and stand back. Befriend a Splicer or two, then move toward the Rocket Turret so you can repair it as it takes damage. Use Insect Swarm on the Splicers that get near the Little Sister to distract them for the Rocket Turret, especially any Fiery Brute Splicers that appear.
Gather #2: Reception
The final Gather Corpse in Minerva’s Den is located in the reception area of Air-Tite Archives, near the customer counters. Place a number of Trap Rivets around the corpse and two Mini-Turrets near the counter behind the corpse to protect the Little Sister. This lets you focus on the more distant Splicers. Befriend any Spider Splicers you can with Hypnotize 2 (or hit a roaming Lancer or Fiery Brute Splicer with the base Hypnotize). Of course, this is also a great time to use Gravity Well. Wait for multiple Splicers to be in proximity of one another, then heave the Gravity Well ball at them. And don’t worry; the Gravity Well won’t affect the Little Sister. Enemies attacking from the doorway will set off the security alarm. Be ready to hack Security Bots to gain allies, while the Fiery Brute Splicers make their appearance.
Before you return the Little Sister to a nearby vent, take a moment to make sure that you collected all of the items in this area. Locate the Audio Diary (“Subversives in the Archives”) on the main floor of the Warehouse. Ascend the stairs to Canister Retrieval on the second floor as you make your way back to the lobby. Electrocute the water, hack the Security Camera, and collect the Audio Diary (“How to Get Ahead”). Return to the lobby and ascend the stairs toward Rapture Central Computing.
Return the Little Sister to the vent at the top of the stairs in the lobby. Quickly make your way to the Gatherer’s Garden in the reception area to spend your ADAM before the Big Sister arrives. Those who have rescued all three Little Sisters in Minerva’s Den will gain the Proud Parent tonic, 50 Dollars, and 100 ADAM.
Big Sister Is Coming!
One way to neutralize the Big Sister’s amazing athleticism is to make her fight you in a tight space. This can be a little risky, but if you wait for her near the window in the reception area by the Gatherer’s Garden, you can force her into a tight space where you can make her step in your Trap Rivets. Splash her with Security Command as she enters to ensure the Security Camera sees her, then open fire with Rocket Spears and Thermal Cells. Hit her with Gravity Well to keep her pinned in one place while the Security Bots open fire on her. She’ll likely call a Thuggish Splicer to her in effort to regain her health, but this also makes her pause, thereby becoming an easier target for you to hit. Collect the 40 ADAM off of her corpse, but consider holding on to it until you get to Operations.
Make your way to Operations and lob the Gravity Well over the wall where the electromagnetic lock is to suck the fuses out.