Whats the greatest game of all time and why?

The Witcher 3 hands down, I've played tons and tons of games of all different genres (puzzle, online mmo, shooters,puzzle games , horror, RPG, ETC ETC) but Witcher 3 is so well done, all the missions doesn't feel like it was just put there to waste time. ALL the sidequest feel well thought out and the NPCs that give them out don't feel just like some background character waiting to give u a fetch quest. I would spend my time hitting every single one I see along the way to the main quest even if it's kind of out of the way because it never feels boring to do.

and also especially in modern times the DLCs they released are MASTER CLASSES better than some games in their entirety.