Well, my particular worryness comes from Flamelurker, a fast moving boss with flame particles and fire blast attack. The enviroment isn't a big deal since Boletaria (I mean Demon's Souls area as a whole) is barren and dark, thanks to the game design (also being a 2008 game doesn't being much of a graphical expertise). I love to be wrong about this though, since playing a Souls game on the go would be very great.