Thunderians were the inhabitants of the planet Thundera. They included the noble ThunderCats.
The home planet of the thunderians was destroyed from within by the sword of plund-darr and what was left of the worlds people scattered, the race becoming nearly extinct.
The nobility of the race the "ThunderCats" eventually crash landed on the planet Third Earth, where they served to protect the planet's benevolent inhabitants from the various dangers that existed thereon.
In all there are 24 confirmed survivors of the planet's destruction, when the world reformed the survivors returned home and established a new colony.
- According to Derrick J. Wyatt, the Omnitrix from the Ben 10 franchise can accept Thunderian DNA, though the resulting transformation would depend on the animal form of the genetic donor and would either resemble some type of cat that has not been seen on-screen or a dog.