The Firebird is a tale told in the traditional quest pattern, in which the hero is called by destiny into a series of adventures. In Ilya's case the call comes first by accident, through the Firebird's curse, and later the whim of an unruly horse.
He goes into an enchanted forest, where he sees wondrous sights and overcomes a series of tests. Finally he comes to a Castle Perilous where he faces his greatest task, the need to uncover a dark secret and to undo evil. The novel's major theme is thus the universal one of good versus evil.
The evil in this story is not a dark force which is simply horrific by definition, as in many horror novels. Rather, its essence is connected to the desire for power.
Both Tsar Ivan and the Katschei are obsessed with power and control, and it has made them oblivious...