The closing scene

In the film it's never made clear. It's not even clear whether the events in the film are the older Merlin's "skewed" version of events, or whether the events in the film are what really happened, and older Merlin told the story differently in the future. The novelisation states that the latter is true- the events throughout the film are what really happened, but in recounting the story, Merlin left Mab out of it because he didn't want to risk her coming back, presumably.

Either way, from what Frik says, we can ascertain that certain parts of the story were definitely true- Merlin and Nimue were in love, Nimue was trapped by Mab's powers (meaning, by extension, that Mab did exist), and that Merlin had a magical talking horse. Anything else, however, would be purely speculation.


Try not to panic. Just think of it as landing a little more vertically than usual