PS1: Final Fantasy VII. No other game has influenced that generation as much as this one. I don't like it as much as I used to, but I still see it as the game of its gen because of that undeniable impact, not because it's the game I liked most (which it isn't).
PS2: Gran Turismo 4. My most played game on the PS2 and the peak of the series so far. It did everything exceptionally well and was approachable in its presentation. To this day, this is the most polished entry in the series by far, even if the newer games included more features.
PS3: The Last of Us. Most mature game I've played. And by mature, I mean in the true meaning of the word. No other game has ever impacted me as much as this one.
PS4: So far, I have to go with The Witcher 3. That game is such a leap above every other games of its type when it comes to the writing of each of its elements. Most other games of its kind should take notes and inspirations from this one. Especially when it comes to side-quest design.
