No, this is not a thread to ask how the rocket turtle works or why was it placed it the Bad Guys section instead of the boss section.

I'm currious why didn't the rocket turtle appear in any official level if it's functional in the vanila version? Does someone know where the rocket turtle was supposed to appear or why it didn't appear?

I don't think it was done. It feels unlikely to me that it wasn't supposed to be able to loop at the very least.

Also he doesn't really do anything IIRC, so he's not that hard to kill.

Though if they made a level like those DevRes levels with the rocket turtle in them?