Darkness

From PMDOWiki

Darkness is a natural feature of dungeons that restricts visibility of the floor. Tiles that have been previously revealed but are not currently within the player's sight will be shaded. Unrevealed tiles will be completely obscured.

Types of Darkness

There are five types of darkness. Additionally, darkness can be set separately for the floor ("Tile sight") and enemies ("Char sight") — this can make it so that the floor is lit but enemies are hidden, or vice-versa.

Image Settings Description
Clear All tiles are fully lit.
Tile sight: Clear
Char sight: Dark
Tiles within line-of-sight are lit. Tiles outside of this are shaded, and any Pokémon standing there are hidden.
Dark Tiles within line-of-sight are lit. Tiles outside of this are obscured until first revealed.
Tile sight: Clear
Char sight: Murky
Tiles within a 1-tile radius are lit. Tiles outside of this are shaded, and any Pokémon standing there are hidden. This most resembles the deep darkness effect in the original games.
Murky Tiles within a 1-tile radius are lit. Tiles outside of this are obscured until first revealed.
Blind No tiles are lit. Only tiles previously stepped on are shaded, and all other tiles are obscured.
Any Out-of-bounds is obscured, but all other tiles are fully lit. This setting is unused.