They just make existing light sources brighter, but if there are none around, then they are useless abilities. There are some spells, but they only help a little. They have no problems seeing you and targeting you with ranged attacks when you are in pitch blackness The problem with any games that make darkness super dark, is they always fail to make the NPCs suffer from this. Sure there is the lantern thing, but I am playing a stealthy mage. My only gripe is that dark areas are super dark, as in you can’t see anything without a light. Destruction has always been the slowest skill to level, by far.

IE: My destruction is closing in on a skill level of 50 and I am only level 14. They also seem to allow skills to level much faster because of this. I also like the leveling system for questing / exploring rather than the skill based levels.

The enemies are not any harder than vanilla, however, the mod that adds extra enemies to camps/dungeons really helps.