|This article is about a/an monster in Ninpu Sentai Hurricaneger.|
Thunder Ninja Undaigo (雷忍者ウナダイゴ Kaminarinin Unadaigo?, 24): A drum-themed eel Chunin robot, Sargain created him with his research on the Gouraigers to absorb electricity and unleash it with his Space Lightning Taiko Drums. Unadaigo managed to overpower Sky Ninja Shurikenger and the Hurricanegers, keeping them from hitting his weakspot, his lightning absorber. Ikkou and Ishhu attempted to beat him with Taiko style, before assuming Gouraiger form and defeating Unadaigo with their Double Gadget. This ninja was then recreated with a serrated sword weapon. He overpowered Senpuujin and Gouraijin until Shurikenger gave Gouraijin the Kabuto Spear to kill off Unadaigo.
- The sword Undaigo uses in his giant battle is the same sword used by Hell's Gate Prisoner Emboss from Mirai Sentai Timeranger.
- TV Asahi's page on Thunder Ninja Undaigo (from the Internet Archive)
- Toei's page on Thunder Ninja Undaigo (from the Internet Archive)