Light

There is light in the dungeon. Each square is either lit or unlit. Within the range of your vision, you can see any monster or object on a lit square. This works even if the monster or object is on the other side of a room, and even if you must look past some dark squares.


 * Walls limit your vision. You cannot see into another room, unless you look through a suitable hallway.
 * Light is useless when you are blind.
 * There are ways to remove light, such as by using a cursed scroll of light. However, a monster will not attempt any such tactic, will it?
 * It seems that some places, such as water, cannot be lit. You can light the inside of a dust vortex, but that is useless.

There are ways to make more light:
 * permanently, with a scroll of light, wand of light, or the spell from a spellbook of light.
 * temporarily, by switching on a lamp or magic lamp. (Sometimes you might want to switch it off again, because lamps reveal your location to monsters.)