another good bud 1 sitting game (b1sg) is bubble bobble.
there’s a class of game that are by nature complete in a sitting. a good one is pacman ce.
a fighting game single player mode can usually be finished in a sitting if the difficulty can go low enough.
actually, most arcade games can be cleared in a sitting if the machine is in freeplay, and can be great dumb fun if the game is right, for instance the metal slugs.
recently i recommended both inside and superliminal precisely because they’re one-sittingable.
here’s a silly story: the summer before the dreamcast came out, hollywood video offered dreamcasts to rent, with sonic adventure. i think you might’ve had a choice of game, but in any event i chose sonic adventure to play over a weekend. but since the rental didn’t include a vmu, and since the dreamcast didn’t have built in storage (which surprised me), i couldn’t save. so i just beat it in one sitting. i’m not sure if i 100%ed it, but i got enough sonic adventure that weekend to never play it again.
you know what game should be completable in a sitting? pathologic 2. with all its interesting choices and their interesting consequences, it would be nice if you could finish a playthrough in 2 or 3 hours. but then they might’ve had to cut out some of the walking…