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You saw all those computers that DiMA's hooked up to, right? They hold his memories or offload data from his brain. Maybe some combination of both? Well, Faraday asked me to help do some repairs on them. And, you know, I got curious. There's like a century's worth of life experiences in there. And that's when I see it. Data models DiMA has been making. One was the Fog taking over Far Harbor. Another was a nuclear detonation on the island. Plus death counts. What if DiMA is so open and welcoming because he's actually hiding something from us? A plan to wipe out the rest of the island?Kasumi Nakano

Best Left Forgotten is a main quest in the Fallout 4 add-on Far Harbor.

Quick walkthrough

Far Harbor main quest: Best Left Forgotten
Travel to the Nucleus.
Talk with Grand Zealot Richter.
Accept to join the Children of Atom.
Force your way into the Nucleus.
Leads to: Visions in the Fog
Enter the Nucleus Command Center.
Find DiMA's terminal.
Power it up with the switch located behind it.
Use the terminal to access the memories.
Retrieve Memory 0V-9AX0.
Reward: DiMA's memory #1
Retrieve Memory 0J-2NN8.
Reward: DiMA's memory #2
Retrieve Memory 0H-3X0P.
Reward: DiMA's memory #3
Retrieve Memory 0Z-7A4K.
Reward: DiMA's memory #4
Retrieve Memory 0Y-8K7D.
Reward: DiMA's memory #5
Find the marine combat armor shipments.
Reward: Full set of Assault marine armor
Marine wetsuit and tactical helmet
Travel to DiMA's cache.
Travel to the Harbor Grand Hotel.
Travel to the Vim! Pop factory.
Recover the wind farm kill switch code.
Uncover the location of the nuclear launch key.
Uncover DiMA's secret medical facility
Leads to: Cleansing the Land
Leads to: The Way Life Should Be
Reward: 500+ XP

Detailed walkthrough

After obtaining Faraday's program the player character returns to Kasumi, ending Where You Belong and starting Best Left Forgotten.

She will reveal her suspicions about DiMA and give a quest to investigate DiMA's memories, which are stored inside the Nucleus Command Center. Otherwise, the terminal controlling the locked gate to DiMA's memories will remain inaccessible until the player character progresses further in the main questline.

Once the quest has been obtained the Sole Survivor must travel into the command center in the Nucleus to access DiMA's stored memories. They must bypass radiation, protect indexers and circumvent sentry intrusion countermeasures in a virtual, maze-like environment to access to the memories.

Through unlocking the memories, the Sole Survivor also unlocks the coordinates of several locations on the Island to investigate: DiMA's secret medical facility at the Vim! Pop factory, the location of the nuclear launch key at the Harbor Grand Hotel, and the wind farm kill switch code at DiMA's cache.

Quest stages

Quest stages
StageStatusDescriptionLog Entry
50 Gain access to DiMA's terminal
100 Retrieve Memory 0V-9AX0(0%)I've accessed the terminal in the Nucleus that contains DiMA's offloaded memories. I need to use DiMA's hacking program to gain access to the first memory.
102 Move Code Blocks to build a Path for your Indexers
104 Unblock the Decoder Beam to break through the Firewall
106 Redirect the Decoder Relay to hit the Firewall
108 Build and Position the Defense Constructs to protect your Indexers
150 DiMA's Memory #1 Added.I've used DiMA's hacking program to gain access to the first memory. Now I have to gain access to the remaining memories.
160 Uncover DiMA's Secret Medical FacilityDiMA's memories are pointing me to secrets he's hidden across the island. I need to investigate these, as well as access his remaining memories to see what else he's hiding. I'm downloading each memory on a holotape in case I need to review it later.
180 Completed: Uncover DiMA's Secret Medical Facility (This stage is only achieved if the player immediately exits the simulation, leaves the Nucleus, travels to the Vim! Pop factory and discovers DiMA's Secret Medical Facility, otherwise the stages advance to 200.)
200 Retrieve Memory 0J-2NN8 (0%)
250 DiMA's Memory #2 Added.
260 Uncover the Location of the Nuclear Launch Key(The map marker for the Harbor Grand Hotel appears after listening to the converted audio of the memory while in the simulation or by selecting the holotape from your inventory if using console commands to advance this quest.)
300 Retrieve Memory 0H-3X0P (0%)
350 DiMA's Memory #3 Added.
360 Recover the Wind Farm Kill Switch Code(The map marker for the DiMA's Cache location appears after listening to the converted audio of the memory while in the simulation or by selecting the holotape from your inventory if using console commands to advance this quest.)
400 Retrieve Memory 0Z-7A4K (0%)
450 DiMA's Memory #4 Added.
500 Retrieve Memory 0Y-8K7D (0%)
550 DiMA's Memory #5 Added. (The map markers for the Marine Armor Shipments appear after listening to the converted audio of the memory while in the simulation or by selecting the holotape from your inventory if using console commands to advance the quest.)
1000 Nucleus is blown up - fail all memory retrieval objectives
1500 Complete "Retrieve memories" objective
2000Quest finishedQuest CompleteI've retrieved all of DiMA's memories that I could and followed up on all the secrets that I was able to.


  • Only the first three memories are necessary for game progression. The fourth will unlock additional dialogue with Nick, and the fifth unlocks the locations for the Marine armor, which does not spawn unless this memory is unlocked. The objective to find the Marine armor shipments appears in the miscellaneous section of quests.
  • If a player character-placed turret shoots a firewall weak point, the firewall will dissolve. This can be used in the fifth memory to bypass the entire puzzle. See the bugs section for more information.
  • If the Sole Survivor has successfully entered DiMA's secret medical facility before starting the quest, The Way Life Should Be will start as soon as one enters the Vim! Pop factory.
  • Survival mode effects will still apply in the simulations, causing the player character's hunger, thirst and sleep to worsen.


  • PCPC Playstation 4Playstation 4 Xbox OneXbox One During the first memory the indexers will all cluster against the walls next to the orange memory column instead of returning to the access point, until they are destroyed. [verified]
    • FIX: Do not interrupt DiMA's voiceover while he is explaining what to do. Wait for each portion of the voice-over to finish before following the instructions he gives the player. This will prevent the glitch from triggering.
    • FIX: Place blocks where the indexers are congregating next to the orange memory column. They will pathfind correctly back to the access point.
    • FIX: Do not run the game above 60 FPS.
    • FIX: Walk or run against the indexers will prompt them to seek another path.
    • FIX: Make the bridges across the gaps wider than one block.
  • PCPC Playstation 4Playstation 4 Xbox OneXbox One There is a bug that doesn't allow the player to start the memories. The game will freeze in the loading screen with the little loading symbol down in the corner. This can happen on any of the memories, not just one. Reloading to an earlier save might help. [verified]
  • Xbox OneXbox One During the first memory the small green indexers do not move to the orange memory column despite building a usable path. It may affect PS4 and even PC users as it seems to be very uncommon. This is a game-breaking glitch and one cannot proceed further in the quest.[verified]
  • PCPC Playstation 4Playstation 4 Xbox OneXbox One There is currently a bug preventing mission completion. On one's first entry to the simulation, it may be impossible to interact with the blocks one must move to make bridges and clear the path for the beam. Exiting the simulation and restarting the console may fix this. Furthermore, turrets are not unlocked for construction when the game informs the player to construct them, making it impossible for the player's green indexers to make it to the objective. This renders the quest impossible to complete, even after several reloads and restarts. It may randomly resolve itself on the PS4 after returning to an old save. On PS4, returning to the simulation may freeze the game. There is a workaround for this bug by using the blocks to imprison the defensive robots before they enter the area, trapping them where they spawn.[verified]
  • PCPC Playstation 4Playstation 4 Xbox OneXbox One On certain memories the indexers will not load memory past 80%. This is reported for the second and fourth memory levels. Then, when one tries to exit the memory simulation, the game can get stuck where one can save the game but cannot move around. A possible fix to this: If stuck on the fourth memory simulation, leave the keyboard/controller alone until the game recognizes the player as idle. Once it goes to the mode where the player character is looking around aimlessly, it is then possible to move around.[verified]
  • PCPC Playstation 4Playstation 4 Sometimes, the orange data rings will disappear before the indexers are done with downloading the data, making the quest impossible to complete.[verified]
  • PCPC Playstation 4Playstation 4 Xbox OneXbox One On the final memory, placing several Defense Constructs near (or within) the red barrier surrounding the data stream will cause them to fire at the dormant drones, which will then become active. If this persists for long enough, the Defense Constructs will eventually destroy the red barrier itself, bypassing the entire puzzle.[verified]