BABBDI
Metro 2033 / Metro Last Light
Fable
Dark Sector
BrΓΌtal Legend
Artificial Extinction
Rexaura (the Portal mod)


and everything from my favourite studio Caramel Column inc.:
Alter Ego (mobile) (one of the best things I've ever played on mobile and almost on my top 3 generally)
Insectarium: Alternative March (mobile)
Aznana (mobile)
Prolegomena To a Hyperdimensional Interface That Will Be Able to Manifest From Three-Minute Interchanged (pc, but only a demo for now)

speaking of which, my top 3 favourite games in general are:
1. STRAFTAT: An arena shooter by the creators of BABBDI, the community is amazing and it never gets old;
2. Fable: Basically set in fantasy Britain but on a different shaped map. Very progressive for its time, there's a gender swap potion in Fable 2 but I never really played that one. Jack of Blades is my favourite villain of all time;
3. Metro Last Light: A linear story game by 4A Games. The books are amazing too, but the games deviate a little in details. LL is so good because of(1)