Citizen Sleeper

I recommend getting the other achievement related to these endings

first if you’re trying to do this in as few playthroughs as possible due to how the autosave system works. If you get the other achievement first before getting this one, your autosave will leave you right before starting the final step of getting this achievement. However, if you get this achievement without getting the other one first, your game will autosave after this “ending” and you’ll need another playthrough to get the other one.

Prerequisites:

• Complete NEOVEND/Navigator's quests: Free NEOVEND (begins by unlocking the Sealed Maglock, which is found by completing exploration at the Rotunda compass icon), Deal with Hunter, and Deal with Killer. This gives you a Greenway cipher.

• Pay to cross to the Greenway, then use the Greenway cipher in data mode, which will result in you gaining a unique seed.

• Gain acceptance into the Hypha Commune, which gives you access to Riko's quests.

• Complete Riko's quest: Help Riko’s Experiments, which in turn requires you to also complete “Grow Mushrooms.” This results in location “Riko’s growbeds” appearing.

Plant the seed in Riko's growbeds and wait out the 8 cycles. After that, select the Riko icon that shows up on the Greenway. Following some story text, you will be given the option to "Break the thread" or "Follow the thread." Choose "Follow the thread" for this achievement. Confirm your choice with "Follow it." After the credits roll, the achievement will unlock.

You will then be back in the station, free to pursue other quests/endings (except for the ending mentioned at the top as it is mutually exclusive to this ending).