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In the movie Hobbit, The Desolation of Smaug, the band are captured by Silvan Elves and taken to Thranduil's Castle in Mirkwood.

Thranduil confronts Thorin and says, "I too have battled the fire-drakes of the North." In this scene we temporarily see Thranduil's face appear with one eye blind and his cheek missing.

My question is: Is Thranduil referring to a specific battle with a specific Dragon mentioned in the LoTR, Silmarillion or other letters? Is it Glaurung or Ancalagon?

marked as duplicate by user8719, DVK-on-Ahch-To, Monty129, John O, John Rennie Jan 3 '14 at 8:47

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