Why was there only one "Retromutagen ray generator"?

[neatoman]

No seriously? Why did Shredder only ever build one? It's never implied to have been harder to create than anything else in the series, so he could just have built a second one. It isn't because it's fake either, if it wasn't real then he wouldn't have tried to use it himself as a weapon. It sure isn't because the initial plan failed, because there are several other instances where such a weapon could be useful. A weapon against the turtles is also not the only possible use either, as it could be used to revert mutants who turn on him or cure himself if he ever got mutated by accident, not to mention that it would be decent way to bribe other mutants who might want to revert back to human form.

I know they might never have made more than five episodes in the first place, but it is rather strange to treat this device as if it's a unique item that can't be replicated. Even in the first five episodes it's arguable that it's a weird inclusion. Not only could he have made multiple ones and armed his robots with them, he could have thought of the idea much earlier. Instead he creates two new mutants, builds an army of MOUSERS and summon the Rock Soldiers before he thinks simply undoing his accidental creations is the best possible option. What's arguably weirder is that he creates it around the time he also gives Krang his body, something he avoided doing because it was a last resort.

There are a lot of things that are just wrong with the actual plot of season 1, it's "better" because there is some level of progression and consequence that is rarely found in the other seasons, it's just that "better" shouldn't be confused for "actually good" or even "good enough". The ray generator is just one of many things that can be rather easily picked apart like this.

Spoiler:

And yes, I realise simply just killing the Turtles would have been the simplest solution, there's not much reason they wouldn't have been able to avoid this raygun the same way they avoid all other rayguns in the show. I'm just pointing out the problem with the properties of this particular device.