Took it back to the late 90s with Thief: The Dark Project. Sometime back in the early 2010s I got all the way up to the very last level and just... stopped. Always intended on returning to finish it or play the sequel at the very least someday. It's rare that I use video games to take my mind off things but there's been some drama going on in my life lately, which caused me to leap back in; the game has been near therapeutic, oddly.
The atmosphere, combined with the way you immerse yourself and engage with the game in order to navigate the levels for your goals are a huge part of the reason why.
This is a total conversion mod for Skyrim, and it's really good.
Special Edition is just because this version requires you to own Skyrim SE instead of the original game, this mod runs a lot better with the SE