Ugh...you really want the fog of war? Like on the map while exploring? Because in my opinion it's such a bad effect, it ruins the exploration and doesn't let you appreciate the environment.
It could work if it only hid enemies and chests or what's behind a closed wall.
Definitely. Outdoor fog of war isn’t generally necessary, but in dungeons it makes sense. Being able to see a room with no obvious entrance is lame. What’s the point in having a secret door if the room it leads to isn’t secret at all?