Revelations 15:1 Moderate

Revelations 15:1
"15:1 And I saw another sign in heaven, great and marvellous, seven angels having the seven last plagues; for in them is filled up the wrath of God."

According to Demon: The Fallen, the War in Heaven began when an angel named Ahrimal foresaw a disaster in the future - a disaster which God had either directly orchestrated or would allow to happen. The angel Lucifer was the first to make a conclusive decision in favor of rebellion, and he became the leader of the rebel angels.