Board Thread:General Discussion/@comment-4539970-20130408164745/@comment-3412412-20130408182756

Ben can't change into a Anodite via Omnitrix because Anodites have no DNA, there are made of energy. Gwen has "the spark" meaning she can turn into her Anodite form, Ben doesn't have "the spark" so he can't turn into a Anodite.