Fallout New Vegas (pure vanilla with not a single mod aka the console editions and the broken PC ports).
It's sometimes hard to recommend FNV to other people due to the fact that the only way to really enjoy the game is using the Viva New Vegas modlist.
I'm never reinstalling Windows so I have to pray that MO2 gets ported to Linux sooner rather than later because I personally despise hacking with WINE prefixes/organizing esps/ESM files myself. Also the fact that
- Mods are distributed through a proprietary network ~~shithole~~ service called Nexus Mods
- I own a copy of the game on Steam unfortunately and I know how much I despise interfacing with that program.
- There's so many mods to install goddamn