It honestly depends on what game in is for me. If it's something like, Black Ops, W@W, BF3, Halo Reach then I couldd only probably play up to a most of 5 hours, yet if it was something like CoD4, Halo 3, MW2, Saints Row 3 I can play all day everyday if I have people to play with. I count myself as quite good at quickscoping as it's pretty much all I do all day. xD
I can play Transformice for as long as I need to
Excluding restroom trips.
Ive done like a 30 hour run during the summer. I used to get head aches when playing for a long time but now I never do.
once i have completed 11 hours of continuous playing without break
i can sit there and play all day if i wanted to.
i've done a little over 9 hours
I used to be the same way, but it ultimately depended on the game and how much I was into it, the people you hang out with also play a big role in it.
About two to three hours then i go get something to drink then im back.
I can play games for all day long if they are good tbh.
It depends on the game, but if it's an adventure style game I can play it all day.