Abandoned Factory Walkthrough - Persona 2: Innocent Sin
The Abandoned Factory is an optional dungeon found in the Kounan District of Sumaru City. You can enter this dungeon for the very first time immediately after you unlock Kounan District but only the 1st room of the dungeon will be open at that time. The main hallway of this dungeon that connects all of the various rooms has no encounters.
How this dungeon works is there's a total of 6 different doors spread out throughout the factory, each of them are marked with a number on the door. As you progress through the game the doors will become unlocked starting with the first and ascending from there.
In each of the rooms throughout this dungeon you will encounter enemies that you have battled from previous dungeons. Aside from unique and quest NPCs there are no new monsters inside of the Abandoned Factory. This dungeon is the only dungeon that stays open throughout the entire game, you can access it and the enemies within at any point. Making this a great grinding location for things like Tarot Cards.
You can also find two hidden rooms in this dungeon, the Executive Suite and the Liquid Waste Disposal. In order to access these rooms you'll have to fully explore this dungeon and read each of the Notes that are hidden in the various rooms. Then spread a rumor once you've read all of the notes; more info on this is found below.
Below is a quick list of all 6 rooms and when they become unlocked.
Executive Suite: Read Note #11 and you'll learn about a rumor involving a hidden switchboard. Get into fights with demons and form Pacts with them so that you can ask them for information, eventually you'll learn a rumor about the hidden switchboard which you can then spread through demons in this same room. More information about this is below.
Liquid Waste Disposal: Read notes 12 and 13 to unlock the Hidden Room in the Executive Suite then fall through the floor into the room. In the Hidden Room you'll have to read note 14 to learn of the rumor involving this room. Head over to Room #6 and make Pacts with demons to ask for information, just like we did with the Executive Suite. Collect the rumor about this room and then spread it to make it a reality. More info on this all below.
There are many different rewards that you can collect throughout this dungeon in each of the rooms. Rewards range from various items that are found in the dungeon to random encounters with a rare enemy and a unique drop once you defeat them. There are also numerous rumor side quests which take place inside of this dungeon.
In addition to the aforementioned rewards - this dungeon is also where you'll find Tatsuya's Ultimate Weapon and Lisa's Ultimate Weapon. Although, getting both of these Ultimate Weapons will require access to the entire dungeon and the spreading of a rumor or two. For more information about how to obtain those ultimate weapons I recommend you check out their specific pages.
Once you gain access to Room #6 you'll be able to unlock the Executive Suite and the Liquid Waste Disposal. To unlock the Executive Suite you'll have to read Note #11 and then form Pacts with demons inside of the room with this note and ask them for information. Eventually you'll learn the rumor about a switchboard in the office that will lead you into a hidden office (pictured below).
After you learn about the rumor of the switchboard from a demon you'll be able to spread the rumor through a demon in the same way. Thankfully spreading a rumor is a lot faster than learning one! You can find the entrance of the Executive Suite inside of Room #4 which is on the second floor of the Abandoned Factory. Inside Room #4 run all the way to the southern end and you'll find the switchboard that leads to the Executive Suite.
Inside of the Executive Suite you'll meet the person who gives you Tatsuya's Ultimate Weapon, Legendary Katana. You'll also find Note #12 and Note #13 inside of this room, both of these are required to unlock the next secret room and obtain Lisa's Ultimate Weapon.
There is one more secret room inside of the Abandoned Factory called the Liquid Waste Disposal room. To unlock the Liquid Waste Disposal what you'll need to do is read both of the notes inside of the Executive Suite then head back to the first floor of the Abandoned Factory. Remember the note in the main hallway by the front entrance of this dungeon? Head to that room and directly south of this note you'll find a hole that you can fall through in the floor.
You'll find yourself in the basement area of the Abandoned Factory; in here you'll want to open the locker to battle Alice, a very powerful demon. You'll also want to read Note #14 which is required to unlock the Waste Treatment room. Once you've read this note you'll want to return to Room #6 and ask demons for information until you learn the rumor involving the Waste Treatment room (pictured below).
Just like before, once you learn this rumor you'll want to spread it through demons the same way. Once you spread the rumor head to the southern portion of Room #6 and you'll now be able to go through the door which was previously locked. This room is the rumored waste treatment/liquid waste disposal room.
Follow the catwalks throughout the Waste Treatment room and you will eventually find a door that leads you into another room with someone named Reiji inside. Talk with Reiji and you'll get Ginko's Ultimate Weapon, Legendary Gloves. Once you've obtained Lisa's Legendary Gloves you're officially done with the Abandoned Factory dungeon! All that's left of this dungeon is the few rewards mentioned below - if you haven't already collected them.
Rumor & Persona Rewards
This section of my guide contains a list of the various Rumor Side Quests and the Persona Material Cards that you can find within the Abandoned Factory. In addition to the items mentioned below you should also keep in mind that each room of this dungeon will typically have items that are not listed on this page.
Room 1: Dresser Hag Rumor Side Quest
Room 2: Cursed Taxi Rumor Side Quest
Room 2: You can encounter Sakya here which drops the Buddha's Words Material Card; you can use this Material Card to summon Sakya in the Velvet Room.
Room 3: Cursed Escort Rumor Side Quest
Room 4: You can encounter Nezha here which drops the Pao-Pei Material Card; you can use this Material Card to summon Nezha in the Velvet Room.
Room 5: Kudan Rumor Side Quest
Room 6: You can encounter Izanami here which drops the Netherworld Path Material Card; you can use this Material Card to summon Izanami in the Velvet Room. Odin can also be encountered here, he drops the Rune Monument Material Card which will allow you to create the Odin Persona in the Velvet Room.
Executive Suite: Virochana can be encountered here which drops the 1000 Lotus Petals Material Card; this card can be used to create Virochana inside of the Velvet Room.
Liquid Waste Disposal: Gaia can be encountered here which drops the Cradle of Creation Material Card; this card can be used to create Gaia inside of the Velvet Room.