Please answer the following question: Build a movie plot around this: What destroyed the castle? The cauldrons magic
A:
In the land of Prydain, Taran is an "assistant pig-keeper" on the small farm of Caer Dallben, home of Dallben the Enchanter. Dallben learns that the Horned King is searching for a mystical relic known as the Black Cauldron, which is capable of creating an invincible army of undead warriors, the "Cauldron-Born". Dallben fears the Horned King may try to steal his pig Hen Wen, which has oracular powers, and use her to locate the cauldron. Dallben directs Taran to take Hen Wen to safety; unfortunately, Taran's foolish daydreaming causes Hen Wen to be captured by the Horned King's forces.Taran follows them to the Horned King's stronghold. Along the way, he encounters the small, pestering companion Gurgi, who joins Taran on his search. Taran leaves Gurgi to sneak into the castle and rescues Hen Wen, who flees, but all too soon he is captured himself and taken to the courtroom, found guilty and thrown into jail. A fellow captive named Princess Eilonwy frees Taran as she is trying to make her own escape. In the catacombs beneath the castle, Taran and Eilonwy discover the ancient burial chamber of a king, where Taran arms himself with the king's sword. It contains magic that allows him effectively to fight the Horned King's minions and so to fulfill his dream of heroism. Along with a third prisoner, the comical, middle-aged bard Fflewddur Fflam, they escape from the castle and are soon reunited with Gurgi. Upon discovering that Taran has escaped, the Horned King orders his dwarf companion Creeper to send the Gwythaints to follow Taran and bring him back alive.Following Hen Wen's trail, the four stumble into the underground kingdom of the Fair Folka group of small fairy-like beings who reveal that Hen Wen is under their protection. When the cheerful, elderly King Eiddileg reveals that he knows where the cauldron is, Taran resolves to go destroy it himself. Eilonwy, Fflewddur, and Gurgi agree to join him and Eiddileg's obnoxious right-hand man Doli is assigned to lead them to the Marshes of Morva while the Fair...