Thundera

Thundera was the prosperous home planet of the Thunderians, a race of cat-like humanoids, and the seat of the noble ThunderCats. It was a world rich in resources and advanced civilisation, but its existence was tragically cut short. The planet was also home to the "Treasures of Thundera", mystical artifacts such as the Sword of Omens and the Book of Omens, which were central to the ThunderCats' heritage and power.

The planet's destruction was a pivotal event, serving as the catalyst for the entire ThunderCats saga. In the original series, Thundera was destroyed after the ancient warrior Jaga cast the evil Sword of Plun-Darr into its molten core to prevent its misuse, an act that ultimately caused the planet to tear itself apart. This cataclysm forced the surviving ThunderCats to flee in their flagship, the Feliner, leading them on a perilous journey to Third Earth.

Centuries after its destruction, the remnants of Thundera eventually reformed into a new planet known as New Thundera. The ThunderCats later returned to this reformed world, using powerful technology like the Gyroscope to stabilise it and begin the process of rebuilding their civilisation, albeit under constant threat from their enemies.