Last night I started up another game of E4 with the intention of a marathon. Along the way I discovered that the maximum overdrive is 380 and the maximum multiplier is 100. The music started getting a little stale after about 4 hours, but it's integral to the game so I couldn't just play some other music. I took a few pictures along the way. The last one I took in game was at 7 hours 18 minutes (duration is the bottom left corner).

Ten minutes later I crashed, which resets your overdrive speed and multiplier. The sun had already come up and I was getting tired and really sloppy. At this point I stopped worrying about keeping my time up and mostly let chains run out even if I was low on time. I could have kept it going longer if I weren't so tired, but I still managed another 30 minutes. I did take a few 5-10 minutes breaks for food and bathroom and such, but my actual game play time was about 8 hours long. Got a good final score on the leaderboards.

So excluding RPGs, FPS, and such, what's the longest you've played a single game or round on 1 'credit'?