20. Minecraft
Notch's extraordinary building blocks game where the only limit is your imagination changed everything, beginning with the concept of open-world exploration and building things. The users of Minecraft are some of the most incredibly talented gamers, having built versions of famous pop culture items within their world. You haven't quite lived until you've seen someone build the S.H.I.E.L.D. Helicarrier in Minecraft. https://www.youtube.com/watch?v=r0ckycD2ZRk The "no rules, no limitations" concept began to lift off into other games as soon as Minecraft hit it big, and it has inspired a slew of imitators. It brought back that sense of playfulness, with just enough tiny hints of danger to keep you honest. Minecraft's free-form, let's just play a game mentality has changed the way developers look at games and how to present them, where the player is in control.