Dungeon generation does not appear to be random. However, the level designs seem intentional and well implemented with gographically interesting dungeons and open above ground areas. One thing 9th Dawn well is use a limited line of sight / fog of war dynamic complement level designs in a way that increases tension. My perception is that the battery drain is fair. Battery life isn't as good as you'd expect with graphics of this nature but charge should persist for some time. In part because the dungeons and graphics are darker you may want to turn the brightness up higher than normal. Playing the game, the earthy backgrounds work well for the content but perhaps not for your battery.