(I'm curious and bored today so excuse another one of my ramblings here :P)
Flowing, contemplative, serene. A kind of meditative state of mind is zen-like. Looking back at some of the games that I have come to love over that past couple of years, the ones that have the most play time in my library are the ones I can completely absorb myself into. The ones with immersive worlds. The ones that have a certain zen-like trait to them.
Now, absorbing myself into a game doesn't necessarily require immersion, as in a first person game with a VR headset or one-to-one motion controls. It is the combination of interactivity, audio, and visuals that meld together to produce an experience that is entirely unique. One example of a game that performs this is Antichamber. The name itself describes it quite well: a chamber of negative space. The virtual space of the game is chock full of non-Euclidean geometry, minimal aesthetics, and is devoid of much sound aside from ambience. A very calming place where one can think and contemplate on the various puzzles in the game. Although I've never completed the game, the time I've spent in it has been well worth it just to exist in its world.
This doesn't necessarily mean quiet and calm. Sometimes it can be loud and hyper. While not a first person game like Antichamber, Super Hexagon is another game that can be completely absorbing with its bright colors, fast motion, and the tilting and shifting plane on which you move. The game may be a cacophony of stimuli, but a zen state can be achieved in it. Understanding the mechanics is simple but skill is required to survive in the wake of the hypnotizing chiptunes and the constant motion. Reaching hexagon in each level requires lasting just sixty seconds; flowing with the ever enclosing patterns just long enough. In all honesty, it recently surpassed Portal 2 in allotted hours despite me loving Portal 2, finishing all of the levels, and playing it with friends. Super Hexagon might have nowhere near the content of Portal 2 but the simple fact that I can find that of state of mind in the midst of the hectic gameplay is what continues to drive me to play more.
The final example of one of my favorite games with this trait is Dustforce. The game has a ton of levels, including one hundred nine community made maps added in the recent DX update, and replaying these levels is essential to fully enjoying the game. Thankfully, the movement, combat, music, visuals, level design, everything works well together to create an absorbing atmosphere that entices one to continue playing, to aim for an SS rank in each level. It's certainly one game that I will continue to play for another hundred hours and not even noticed the time pass by.
All in all, this isn't a statement about the quality of games but just a personal opinion of what I look for in games; the reason why I play certain ones far more than others. Other notable mentions that I want to add here are TRI, Minecraft, Risk of Rain, FTL, State of Decay, Superbrothers: Sword & Sworcery, Anodyne, and Audiosurf (some of which have a kind of monotony that allows for reflection and/or easy multitasking).
TL;DR The games I play most often are ones in which I can achieve a meditative, zen-like state of mind.
Do you guys also look for this in video games? What are some other reasons you like to play a game for dozens of hours on end?