I don't think Dark Souls would be such a perfect fit for a handheld.
The "no can pause the game" asset of Demons Souls was one of the characteristics that made the game so exciting and challenging. I mean, it still can be done, of course. But I still think is the kind of game you need to be total immersed to really enjoy, as your regular thriller or spooky game. Playing it on a train, on a bus or in a McDonnalds just doesn't feel right.







