User blog comment:Dragon´s Blade/World Coexistence Alliance/@comment-98.211.214.12-20140917140254/@comment-98.211.214.12-20140917213002

Rodney: From what I learned, Arcana Shadows appear on nights of the full moon. The reason why is because they can gain a lot of power during those nights. If there is no full moon, they don't get enough power and go into hiding.