The subject of this article originates from non-canonical sources. To find out about what is considered "canon" see LOTR:Canon.
During the War of the Ring, Riodur was among the elves that followed Haldir of Lorien to the fortress of Helm's Deep, in which the Rohirrim and their king were surprised by their arrival. Belurion and the elves were later stationed on the Deeping Wall, which ensured that every fortification of the Hornburg was manned. As the battle started when Aldor accidentally fired an arrow at the Uruk-hai, killing one by hitting him in the neck, Belurion and the elves demonstrated their unmatched proficiency of archery, as they loosened devastating hails of arrows in seconds, killing many Uruk-hai that were charging towards the Hornburg and the Deeping Wall. After the wall was blown by a group of Uruk-hai sappers that laid charges (which were prepared by Saruman) in the culvert under the wall, Belurion and the remaining elves were rallied by Aragorn for a counter charge against the Uruk-hai that were pouring through the large gap that was made from the explosion. He was killed when he was stabbed by Uruk spears.
- Belurion is not seen in the books.
- He is featured in the Decipher Trading card game.