In the original Spectrobes, Thundora can only be obtained through Nintendo Wi-Fi Connection, the only Spectrobe in the entire series that can be obtained through this method. In this game, Thundora is a Spectrobe that only has an Evolved form; Spectrobes: Beyond the Portals gives it its Child and Adult forms.
Thundora is based upon Raijin, the Shinto god of thunder. He has three bell-like rings on its back and thunderbolts that protrude through many parts of its body. it also has tiger-like stripes on its arms and legs. Thundora's design, especially relating to the thunder rings, is based of the thunder god from ancient Japanese mythology. The Japanese kanji "雷" (rai, meaning "thunder") is printed on its shoulders.