Utterdark

The world is covered by a blanket of utter darkness. All living beings must use torches to see even a few feet in front of themselves. During the perpetual night, forces of darkness and roaming shades will attack enemy provinces.

(Worldwide Income and Resources -90%. Caves and deep seas are exempt from the income reduction. All battles are fought under Darkness -6. Demons, blind beings and beings with spirit sight or perfect darkvision are unaffected by this spell.)