Alternate Title(s): ライディーン
Official Website: (Japanese)
Genre(s): Mecha, Science Fiction
Episodes: 26
Opening Theme: "manacles" - Tomiko Van
Ending Theme: "Kakeashi no Ikizama" - Ataru Nakamura
Summary:  "Saiga is a normal high school student with a gift in mathematics. His daily routine is disrupted when his family gets news that his Father's remains have been discovered- a noted archeologist and researcher who had gone missing while exploring a site many years before. Among his remains were notes and artifacts that needed to be identified by the family near a notable triangular mountain in Japan known as "Japan's pyramid", a place suspected by some to be man-made. A meteor containing a strange robotic life form falls from the sky and begins to cause destruction, putting Saiga in danger and causing a mysterious bracelet from his father's research to activate and merge him with an ancient robot buried within the pyramid- a robot the runes describe as Reideen. It is now up to Saiga and guardian Reideen to fight against this unknown alien threat from the sky."

                                   ~Anime News Network, src