Top 20 - All Genres - All Consoles
This is my all-time favorite list. There are many like it, but this one is mine. Note, I was a kid in the NES/GB/SNES and Wolf3d/Doom era, so it'll be flavored accordingly.
How does one compile such a list? My approach was to consider the magnitude of its impact at the time in which it was most influential. Perhaps when it came out (i.e. Myst, Breath of the Wild, Tetris); perhaps much later when I realized how much it mattered to me when I was "way into it" (Metroid Prime, Turtles in Time, Doom); how it will affect the way I play with my kids (Burnout, Rock Band, Galaxy); or all of the above (SMB3, LTTP, SF2).