Build a movie plot around this: What does Ergo transform into to kill the slayers? into a tiger
In outer space a large asteroid-like object floats above the planet Krull. It suddenly changes course and lands on the planet. From fissures in the rock pour out a vast army of strange and fearsome creatures called Slayers. They fan out and begin to terrorize villages and cities. The ruler of the Slayers and inhabitant of the asteroid, called the Black Fortress, is a hulking alien being called the Beast. A voice, belonging to an old man name Ynyr speaks of a prophecy that one day a young prince will possess the power to defeat the Beast. Until the prophecy can be fulfilled, Krull will endure years of terror from the Beast and his armies.The young prince believed to be Krull's savior is Colwyn. He is betrothed to a young woman, Lyssa. The prophecy also speaks of the prince's bride being born with an ancient name and that she and her husband shall rule the universe if the Beast is defeated.Colwyn rides to his bride's father's castle for the wedding. He and his father & their party are delayed because the roads they travel are dangerous and there are regular patrols of Slayers. When they arrive, the marriage ceremony is put into motion. Just as the bride and groom are about to complete a tradition of exchanging a flame the Slayers attack the castle and interrupt the ceremony. Colwyn and his father and his father-in-law-to-be mount a valiant defense but they are vastly outnumbered. Lyssa is captured, Colwyn's father and the bride's father are slain and Colwyn himself is wounded and left for dead.Some time later Colwyn is found by Ynyr, who takes him to a hidden location to tend to his wounds. He tells Colwyn of the prophecy and that he is the prince that will save the planet. However, Colwyn must save Lyssa from the clutches of The Beast, who has taken her back to the Black Fortress. Colwyn scoffs at the plan since it is widely known that with each sunrise on the planet the Black Fortress changes location and never appears in the same place twice.Ynyr seems undaunted by the ubiquitous nature of the Black Fortress...