He is a knight owns an weapon on his right hand to attack the opponents, he is a Bakugan with an high intelligence that he can use to target the rivals who want to use the Bakugan for malicious purposes for no reason.
Cyndeous was first seen as Drago's rival, but after he got defeated, he becomes his ally and helps him to protect the Bakugan from device that previously mind-controlled harmless Bakugan for selfish purposes.
Despite his giant appearence, Cyndeous likes to protect Kelion, Drago and all of good Bakugan from malicious thugs who want to control these harmless Bakugan for selfish and malicious purposes for an unknown reason. He also likes to free the Bakugans from device that makes Bakugans cause destruction for no reason.
He was victim from an goo that turns him into a Bakuzon sent by Tiko who was the main antagonist from the show, after being cured from the V-Virus, he has no memories of being infected by the goo that causes the Bakugans to be destructive and aggresive for no reason.