Pathologic 2

Just climb to the top of the Polyhedron. I had access to it on Day 8, and it worked, but most guides say Day 10. Do it as soon as it is available though, as it becomes a significant plot device in the later days and is harder to access.

There's a quick way to unlock all the achievements using commands on PC
Shout out to RAILBAIT for finding this method
This game is on game pass and it's Xbox play anywhere so you can play it on Win10
This method only works on Win10 unfortunately

When you are on the main menu
press control+shift+f4
Which will bring up a menu
While that menu is open type "Unlock_all_achievements" at the bottom
press enter
Then type "Unlock_achievement"
press enter again
Then type "save_game"
go to the main menu
press control+shift+f4 again
Then go to >Inspector
go to >Services
Then drop down >Element 0 (Achievement Services)
Open that
Open the top option that says >Service (AchievementServiceXboxLive)
Click "Unlock All"

If needed check out my video below :)

Achievement Walkthrough - Quick Method: