The original season of Bakugan Battle Brawlers might be a bit of a biblical allegory. While raging about how religious nutcases say that anything fun is "Teh Debil", I realized that there is actually a surprisingly literal allegorical Satan(Naga, appropriately named after the serpent) down to trying to steal the powers of heaven, failing, and being hurled into a torturous realm from which he acts, and Mephistopheles (Masquerade) Who tempts people who play the game into using it for evil in very devilish ways (Note: These are the BAD GUYS). While some demonize it, a subtext of the show is ironically resisting satan. - Kohdok
Drago's power has been constantly increasing the entire series. The first thing the newest season has happen? His increasing power result in the season's entire storyarch. Its threatening to set Mag Mel, the Big Bad whose presently Sealed Evil in a Can, free from his prison, causing Dan and the other Brawlers heck by creating a Nigh Invulnerable monster whose running around beating everyone to a pulp without even trying, and ruining Dan and Drago's reputation completely because Drago can't control it. Makes sense when you realize that fans had been complaining a great deal about Drago's ever increasing power. What better way to appease fans by deconstructing the thing they're complaining about?
A lot of Mag Mel's actions make a lot more sense after The Reveal that he was Emperor Barodius.