Attacks by creatures affected by Darkness have their base Hit Rate decreased by 20% (40 points), and attacks made against them have their base Hit Rate increased by 20% (40 points). Darkness wears off at the end of combat. It can also be cured with the LAMP or CUR4spells.
Attacks by creatures afflicted with Darkness have their base accuracy decreased by 40 points, and attacks made against creatures afflicted with Darkness have their base accuracy increased by 40 points. Darkness wears off at the end of combat. It can also be cured with the Lamp or Cure4spells.
Darkness halves the target's accuracy, evasion %, magic accuracy, and magic defense %. It's easy to remove with Esuna 1, but in addition to the deleterious battle effects, characters afflicted with Darkness will not gain any progress after battle.