Perdition is one of the final quests that conclude the story of Prey and a pre-requisite of an ending that involves acquiring and using two arming keys to initiate the autodestruct procedure for Talos I. Furthermore, you'll be able to decide whether you want to be a martyr or escape the station before it is reduced to dust.
Warning - Choosing this ending forbades you from going through with Mind Without Limits, an ending that involves using a nullwave transmitter to destroy the Typhoon without having to destroy the station.
- Acquiring Alex's Arming Key
- Accessing the Reactor Console
- Applying the Arming Keys
- Initiating the Auto Destruct Procedure
Acquiring Alex's Arming Key
The quest is activated in the final part of The Keys to the Kingdom, i.e. when met with Alex Yu w Arboretum. You can listen to what Alex has to say (initiating Mind Without Limits) or simply engage him in order to get access to the key. If you've delayed your move, the appearance of Apex will throw Arboretum into a state of zero gravity, either killing or incapacitating Alex. Use the opportunity to search his body to acquire Alex's Arming Key (you already have the first key, which was found in the course of The Keys to the Kingdom)
Note - If by any chance you've lost one of the arming keys, you can use a fabrication plan to develop a new one. The plan for Morgan's Key could be found during Reboot, while Alex's Key Fabrication Plan is found on his body. You cannot use the fabricator in Arboretum, but you can make your way to e.g. Talos I Lobby and reach a similar device in Yu's office.
Accessing the Reactor Console
Morgan has to travel to the Power Plant. As a reminder - the area is accessed through Life Support, which means having to use the Arboretum elevator. The zero gravity environment in the area means having to limit the flight time to a minimum and avoid Apex's tendrils which can be driven off by activating the available nullwave transmitters. Moreover, the path ahead is guarded by military operators and powerful Phantoms - consider sneaking past the opponents that don't obstruct the way forward.
If you've managed to reach the power plant, make your way to a nearest grav shaft and use it to access level -5. The reactor control room is accessed by using the maintenance access shown on the screenshot above.
Applying the Arming Keys
Make your way through the maintenance tunnel that leads to the area below the main reactor. The console contains two sockets used to hold the arming keys (you can see both on the screenshot above). Place a key in each socket (your hero will apply the right key by himself) and twist both.
Initiating the Auto Destruct Procedure
You now have to use the command console found on Talos I Bridge. The area is accessible through Arboretum, so you'll be subjected to a second trek through the zero gravity zone. Make your way to a grav shaft that allows you to access the bridge and accept the destination.
Proceed to Captain Jada Marks' cabin located on level 3. Your destination (the command console shown on the screenshot above) will enable you to interact and begin the autodestruct procedure. A countdown will begin, giving you a short window of opportunity to do your final bidding.
You are now left with two ways of proceeding. If you want to be a hero, you can wait for the countdown to end or (a better idea) sit on the captain's seat to end matters faster.
Alternatively, you can escape from the station by boarding Dahl's shuttle stationed in the Shuttle Bay. This variant is available only if you've went through with Incapacitate Dahl i.e. you've made the admiral switch teams and "recruited" a shuttle pilot in progress. The time limit offers only a narrow window of opportunity - focus on sprinting throughout the following areas and avoid getting into fights with the remaining typhoons or operators. Once you've reached the shuttle, proceed to the cockpit and sit next to Dahl.
The game ends regardless of the chosen variant.
Warning - Do not turn off the game yet, as the end credits (you can skip them by pressing one of the buttons) are followed by an epilogue which contains a summary of your choices and actions, including the accounts of people who you've saved or gotten rid of.
Finally, you'll be left with a final choice - you can everyone still alive on the station, or take Alex's hand in friendship.