Outer-Wall Ruins – Ancient Machine Works is the eleventh area of the game. This area includes a back entrance to the jail area you were transported to if you died to the Hunter of Bladers boss, or a way to explore that area if you didn’t. It also includes the hidden boss Ursula, the Mutant who you are required to beat for two of the endings. The walkthrough also includes the short third part of Underground Parish that occurs immediately after exiting the Ancient Machine Works where you have the fourth interaction with Feylia.
Outer-Wall Ruins – Ancient Machine Works
Factory Bypass
Key Item: Dew Essence – Follow the main path until you drop out of a pipe into an area with paths going left or right. Take the ramp up to the right and follow the path to an open area with a big Sewer Cleaner miniboss. Defeat it, then pick this up beside the snail shell in the back corner.
Go back and follow the path leading left to continue to the next Branch.
Assembly Hall
Normal Seal: Submerged Coffin – In the room with the laser robot, go down the right side to the second room where you can climb a ladder to the upper level. Go back toward where you entered and you can enter the room overlooking a platform with this pickup.
Spell: EX-Railgun – Obtained automatically after you destroy the big laser robot by breaking the 4 tubes around the room. One each are on the upper paths on the left and right, one is at the back of the robot, and the final one is up in the walkways by taking the ladder immediately left of the robot before going through the doorway to progress. If you want before destroying it you can use the laser it shoots to deal with the enemies in the room, as it will do significant damage to the large Sewer Cleaner minibosses if it hits them.
Item: Alcohol – Continue past the 4th tube on the walkway and then go into the room in the hallway, this is in the corner behind some boxes.
Item: Alcohol – Continue to the end of the hallway and in the room past the stairs leading back down you can find this on the shelf.
Material: Iridescence – Go back to the walkway in front of the robot where it was spraying fire at the ground. With it no longer active you can drop into the below area and pick this up at the far side.
Key Item: Ward Key – Continue down the hallways then enter the first room on the right. On a shelf by a robot you can pick this up.
Continue down this hallway to reach the Prison area you entered if you died to the Hunter of Bladers boss.
Shirley’s Room
Normal Seal: Tyrant – With the Ward Key you can now unlock the doors in the area around Shirley’s Room. Open the door on the right side (from where you entered) to find this by a note.
Item: Alcohol – On the bottom level, go to the door on the back right where this is on a shelf in the room with the three human enemies.
Normal Seal: Nova – Continue along the main path past the hallway leading to Shirley’s Room, and interact with the Memory by the consoles.
Hidden Area: Underground Lab – Go back to the long bridge over the abyss after the big robot. Look below to spot an item on a pipe. You need to jump out to the closer pipe, then drop down to the pipe with the item, then jump down to the platform below. Make sure to heal in between drops so you don’t die on the way down.
Research Center
Key Item: Observation Report – In the room with the Branch.
NPC: Assis – Return to Assis at the Temporary Campsite and interact with him to earn 
A Deadly Joke Assis questline #2
Hidden Boss: Hunter of Bladers Ursula/Ursula, the Mutated
Trophy/achievement 
Ursula
Armor: Blader Huntress Attire – Obtained automatically after defeating Ursula, the Mutated boss.
After defeating her go to the back of the room and interact with Ursula and exhaust her dialogue. You will need to interact with the Branch, then speak with her again, finally prompting you to kill her.
Key Item: Living Seed – Obtained after speaking with Ursula by the Branch. DO NOT GIVE THIS TO DELPHA if you are planning to earn all three endings this playthrough. AI Limit Endings & NPC Questlines Guide
Key Item: Laboratory Key – Obtained after killing Ursula.
Nuclues: Mutant Blader Nucleus – Obtained after killing Ursula.
Playing into NG+ is required to obtain a second Nucleus to purchase both of these weapons.
Weapon: Red Deer – Purchase from Assis for Mutant Blader Nucleus + 10,000 Crystals
Weapon: Mercy – Purchase from Assis for Mutant Blader Nucleus + 10,000 Crystals
Undergound Lab
NPC: Adrammelech – Go into the next room and speak with Adrammelech, then kill him once he starts attacking you. Adrammelech questline #3
Key Item: Adrammelech’s Badge – Obtained automatically after killing Adrammelech.
You can then take the elevator behind Adrammelech to reach another train station, which transports you to the final part of the Underground Parish.
Sunken City Underground – Underground Parish
Living Pond
Nucleus: Cleansing Knight’s Nucleus – Obtained automatically after defeating Cleansing Knight miniboss along path leading to Trial Hall.
Trial Hall
NPC: Feylia – Speak with Feylia right beside the Branch, accept her help to fight the boss ahead, then speak with her again to start the fight. Feylia questline #4
Boss: Eunomia, the Resplendent Bishop
Key Item: Vessel Remains – Obtained automatically during the Resplendent Bishops boss fight.
Trophy/achievement 
The Resplendent Bishops
Trophy/achievement Fair Fight (for beating the boss with Feylia’s help)
Nucleus: Divine Vessel’s Nucleus – Obtained after defeating Eunomia, the Resplendent Bishops.
Normal Seal: Monolith Form – Speak with Feylia after defeating the boss to obtain this seal.
Material: Iridescence – At the Temporary Camp Assis now sells 1 Iridescence for 15,000 Crystals.
Material: Hereditary Resonance – At the Temporary Camp Millaire now sells 1 Hereditary Resonance for 10 Adaptive Fragments.
Playing into NG+ is required to obtain a second Nucleus to purchase both of these spells.
Spell: Lightning Hammer – Purchase from Millaire for Divine Vessel’s Nucleus + 7000 Crystals
Spell: Lightning Cluster – Purchase from Millaire for Divine Vessel’s Nucleus + 7000 Crystals
Go to the back of the room and behind the large statue to find the next Branch.
Bishop’s Passage
Interact with the portal to proceed to the next area.
Next up: Hagios Patir – Upper Level & The Sphere – Elysium
For all other areas refer to the AI Limit Walkthrough.
Basil Heim says
I just wanted to let you know that this specific Part in your Guide may be different:
“Nuclues: Mutant Blader Nucleus – Obtained after killing Ursula.
Playing into NG+ is required to obtain a second Nucleus to purchase both of these weapons.
Weapon: Red Deer – Purchase from Assis for Mutant Blader Nucleus + 10,000 Crystals
Weapon: Mercy – Purchase from Assis for Mutant Blader Nucleus + 10,000 Crystals”
What i did:
– killed the boss
– talked to her
– severed the branch
– talked again
– i repaired the branch (the one we sever to kill her)
– teleported to campsite to exchange one weapon
– got back to the secret Lab and a Mutant spawned right there. He dropped another Mutant Blader Nucleus on Death that I exchanged for the other Weapon
Gage says
To confirm, you left immediately from the Branch instead of going in and speaking to Adremmelech? I checked on my post story save and there’s nothing in there, but maybe it’s some extra thing if you ignore Addremelech and don’t kill him before leaving the area.
Vash says
I just don’t have the heart to not honor her request and let her turn into a mutant. But it’s your choice and the game is great that it gives you the choice. I’m planning on multiple ng+ anyway but for people who just want to play and get 2 nucleus in 1 playthorugh this is great advice for them.
Ben says
Nah doesn’t work. Made a save beforehand and tried it different ways, beating her 4 times. With and without talking to Adremmelech.
Nothing spawns unfortunately.