The four existing seasons of Bakugan (Bakugan Battle Brawlers, Bakugan New Vestroia, Bakugan Gundalian Invaders, and Bakugan Mechtanium Surge) aired between 2007 and 2012.
Since then, there have been Bakugan reboot series titled "Bakugan: Battle Planet" (2018-2019) and "Bakugan: Armored Alliance" (2020-2021), which are considered separate continuity from the original series.
To stay updated on the latest news and announcements about Bakugan, I recommend keeping an eye on the official Bakugan website, social media channels, and reliable entertainment news sources.