Gundalia is the Gundalians' home world, located in an unknown galaxy (possibly Centaurus A). The city is underground and has been ruled by Emperor Barodius' family for several generations. This also home some breeds of Bakugan, born from ancestors that left Vestroia. It is a wasteland. It appears to be a swamp. Most Bakugan on Gundalia are of the Darkus Attribute.
It also appears that the Gundalians and Neathians are very good friends now, seeing how well Paige and Rafe battle and work together. However, it appears that a few, like Anubias, still have evil and dark intentions.
In A Hero Returns, Barodius (reborn as Mag Mel) started to attack Gundalia to get revenge against his former servants.