>>9898931if you ask me it comes down to an inconvenient fact about ben 10, too many aliens. I think alot of them fill similar roles, but because they look cool everyone forgives that. Im not even saying thats a bad thing, after all the aliens are the life blood of the franchise, but because there are so many, and so many more are capable of similar feats alot get left behind. This happened alot in UA and AF. Ripjaws got replaced by Water Hazard, Greymatter by Brainstorm, Diamondhead by Chromastone, etc. It's an issue that spilled over into every series thereafter too. So by the time you get to Omniverse, there's a dozen different flying aliens with the ability to fire some kind of ranged attack, that Jetray gets left in the dust.
Then you factor in all the aliens Omniverse introduced and it's only natural that you'd see less and less from then more obscure aliens like Lodestar, Amphibian, Swampfire, etc because theres just too much competition by that point already. By the time you get to the reboot the aliens ben uses just feel like the greatest hits of the franchise upto that point.