bakugan

A toy and anime franchise launched in 2007 that centers around the eponymous creatures known as Bakugan. They take the shape of balls that transform into beasts when thrown into battle. The story generally revolves around the Bakugan home planet known as Vestroia coming into contact with Earth and humans meeting the Bakugan.

The original Bakugan anime ran for 4 seasons:

Bakugan Battle Brawlers
Bakugan New Vestroia
Bakugan Gundalian Invaders
Bakugan Mechtanium Surge

The anime was rebooted in 2018 with the first season titled;
Bakugan: Battle Planet

And again in 2023, simply titled; "Bakugan".