In short, Now the fourth season will never be dubbed.
Which introduces a Dub-Induced Plot Hole when 4Kids dubbed the recent movie since the dub makes it look like Jaden sacrificed himself to save everyone which leads some people to wonder how did he come back and why is he carrying around Banner's cat.
Only the first season was ever released to DVD in the US.A. but those discs are now extremely rare and quite pricy, especially the Second half of said season.
Averted as of October 2014, The entire 1st season will be released on DVD by New Video Group, also the first 3 seasons are available on Hulu.
What Could Have Been: Commented on In-Universe between Zane and Aster; Zane wished he could have dueled the Supreme King as his Worthy Opponent and it's also implied that Aster would have dueled the Supreme King to save Jaden, since he owed a debt to help him.