Angela Lalonde: Katamari Forever. Rolling up items, including worlds, to reach certain goals, can be exciting or calming depending on your mood.
Alex Cox: The Witcher 3. An immersive storytelling masterpiece that throws the very worst (and the best) of humanity right in your face. It's bloody, beautiful and inspiring. I suppose the original Mass Effect trilogy would be a close second for similar reasons.
Wale Lakeru: The Legend of Zelda: Breath of the Wild. Nintendo are craftsmen of the highest order when it comes to level design. They essentially took that, and multiplied it by 50 with this new iteration of Hyrule. Coupled with outstanding AI, great battle mechanics, a beautiful soundtrack, tight controls, and clever dungeons. It just takes the cake for me, personally.
Madison McElroy: Superliminal comes to mind. The mechanics are so interesting and visually it's so fun (and challenging). Plus, the narrative throughout always gets me emotional at the end. Very thoughtful game.
Derek Dobell: World of Warcraft and the Diablo series — kind of owe it all to Blizzard.
Kevin Kelly: Metal Gear Solid 2 is the Citizen Kane of video games
Ted Hill: Asteroids Deluxe. With the shield instead of the earlier "hyperspace" that always got you killed
Brandon Warren: Kingdom Hearts and the EA Sports NHL series.
Madison Andrus: Zelda Breath of the Wild. No explanation needed.
Dave Nordby: Pong really rocked it. I am too busy reading books to expand my mind than to play video games!
Timothy Brown: Metroid Prime or Resident Evil 4♦