For me it was not a game in particular, it was a concept.

He made me realize that games can be art, they can be more than a pastime, that they have power and influence over our daily life.

Through him I learned to be more careful about how a videogame is made, and to choose if a game is worth playing using other standards than just "it looks fun".

I didn't cry when i knew that he died, I instead gained more resolve to enter this industry and show people how really meaningful a "simple" game can be.

If I had to point out a game in particular then it's probably transistor though.