What is the best video game of all time for you, and why?

My current favorite game is Warframe, but I think the best of all time (that I've played, I'm sure some classics are superior) would be Minecraft. You may laugh, but I've gotten more time out of Minecraft than any other game comes close too - due to the depth of community maps and mods, it has infinite replayability.

(I also think Halo as a franchise has had an incredible impact and would be my second choice)