Soldato
Probably World of Warcraft. Even though I don't play it.
Having genuinely played PC since... well duke nukem/doom/C&C/Dune 2 days...
I'd struggle to find anything that genuinely entertains as much as X-Com 2 with the Long War 2 mod.
Edit: Ultima online was pretty decent though. WoW stole a lot of years from me as well. Still, I think X-Com 2+LW2.
Battlefield 2 ( and expansions) for me. Unrivaled fun and nothing has came close since for me
Deus Ex...all day, every day.
thisHalf Life
Magic Carpet lol