As if it wasn't enough that humans had polluted the seas for thousands of years, they also filled the seas with monsters with huge propellers. Karetta carettas did not want to die on the wheels of these terrible propellers. They wanted to continue their generation forever. They wanted to have their weapons in order to be protected from these dangers posed by people. And they turned into a Robocaretta. They were now more resilient to dangers and quicker to flee.