When a group of ancient star-gazers perished in the Great Plains while attempting to commune with the Thunderbird, their bones were scattered across the prairie and infused with cosmic energy during a powerful storm. Rather than forming a vengeful earth-bound spirit as in Japanese tradition, the Thunderbird's power transformed them into a benevolent celestial entity that bridges worlds. Lyra Stargazer was the first to recognize the constellation-like patterns in its massive skeletal form and established a connection that has guided the Celestial Voyagers ever since.

Standing sixty times the height of a human, the Galactic Gashadokuro's bones are infused with starlight that flows like luminous marrow through its transparent skeletal structure. Unlike its folklore counterpart, it emits no threatening sounds but instead resonates with harmonic frequencies that reveal cosmic pathways when interpreted correctly. Its hollow eye sockets serve as portals through which the Celestial Voyagers can glimpse distant celestial events and hidden cosmic truths. When it moves, it leaves trails of cosmic dust that form temporary constellations, revealing messages from the Thunderbird.

The Galactic Gashadokuro serves as both celestial compass and cosmic interpreter for the Celestial Voyagers, helping them navigate the ethereal currents that flow through the Thunderbird's domain. It reveals hidden pathways between earthly locations and cosmic phenomena, allowing the Voyagers to access sacred sites at moments when the veil between worlds is thinnest and the Thunderbird's messages are most clearly transmitted.