Darkness tokens are placed on a room’s name and affect every investigator in the room. The effects of darkness are twofold:
An investigator who wishes to explore the room must spend an Action Step plus one Movement Step to do so.
An investigator receives –2 to all attribute tests during combat while he is in the room. Note that this penalty is in addition to all other penalties (such as from being stunned).
Some Exploration cards (such as the “Lantern”) allow investigators to ignore these effects. When ignoring these effects, an investigator also cannot be targeted by cards that require them to be in a room with a darkness token.