The theme of the "Lucifer" series revolves around the free will problem. Carey's Lucifer is a figure representing the will and individual willpower, who challenges the "tyranny of predestination". While in Heaven's eyes this is blasphemy, Lucifer points out that the rebellion (and indeed all sin) and damnation as consequence were pre-planned by his Creator, God. Lucifer rejects God's rule and moral philosophy as tyrannical and unjust. The violent, aggressive, totalitarian, vengeful, and dictatorial aspects of Heaven's rule are represented mostly by the angel Amenadiel, who has a particular hatred of Lucifer and leads attacks of various kinds against him. The attacks include verbal criticism, marshaling the host of Heaven, as well as challenging him to individual combat—almost all of it without the slightest care for the countless innocent, unwilling and unwitting victims that he is more than willing to sacrifice for his own pride. For his part, Lucifer disdains Amenadiel, treating the latter's emotional outbursts with contempt, and repeatedly defeats Amenadiel's assaults with well-orchestrated, hidden plans. Ironically, however, it is often difficult to discern when Lucifer acts as a slave to predestination, and when he effectively acts according to his own free will.