Jonathan Segal, also known as Johnathan Shigaru, holds the rank of Brigadier General in the Empire Forces. He assumes command after replacing the ill Brigadier General Collins. His first major initiative involves seizing control of the Genospino project, appointing Aldridge as its pilot, and launching an assault against the Republic. This attack results in his conviction for treason, despite his belief in its righteousness.

Following conviction, Segal resurfaces to aid Dr. Land in completing the Omega Rex project. His ultimate motives crystallize when he publicly announces the formation of the "True Empire" faction in episode 27. He installs Hannah Melville as its leader, declaring her the legitimate heir to the Empire due to her lineage as a descendant of a previous Emperor, directly challenging Emperor Fiona's rule.

Segal builds a significant loyalist army to overthrow the existing Empire. Despite initial setbacks, his influence surges dramatically after securing alliances with the Zero Phantoth and Jamminga forces, making him a formidable threat to the combined Empire and Republic.

His position crumbles when Hannah Melville abandons his cause, stripping his claim to legitimacy. Betrayal by the Jamminga devastates his remaining forces. Cornered, Segal seizes a Regeneration Cube as leverage, demanding Empire and Republic recognition for his faction. The Empire concedes under duress. However, escalating his demands to include personal rulership alienates his final allies, leading to the loss of the Regeneration Cube.

In a final act of desperation, Segal attempts to die as a martyr in battle. Hannah Melville intercepts and captures him instead. His story concludes with imprisonment by the Empire.

Throughout, Segal exhibits fierce loyalty to his vision of the "True Empire," a conviction driving his betrayal of the imperial structure. He is not depicted as a Zoid pilot.