As a Wild Mass Guessing subpage, all spoilers are unmarked as per policy. You Have Been Warned.
The beanstalks create a trans-dimentional portal effect
That would explain how the giant's islands haven't been found in modern times.
The movie takes place in the same setting as Willow
That was actually Willow Ufgood at the theatre. Cloister is Daikini kingdom.
The giants reproduce asexually
There seem to be no female giants in the film. That's because they reproduce asexually by budding, explaining why Fallon has a half-developed second head on his shoulder.
