Quoted from PanzerFreak:
What does this represent from the theme?
I think there are two parallel stories going on. One for each playfield.
On the top playfield you’re helping villagers load catapults to attack the Black Keep and lower its main defenses, allowing you to breach it and fight the Black Knight in the throne room.
On the bottom you’re traveling to different kingdoms and defeating the Black Knight’s minions to steal his power, which helps weaken him during the final battle in the keep.
That’s my understanding, anyway. Could be a really cool story-driven risk/reward concept!