Evox is still a primary villain? Usually, a hidden villain would appear to take over the position as a lead antagonist but I doubt his robot flunkies are planning to betray him. Well, Scrozzle had a slight chance of becoming the next main villain.
Yep. Only instead of a holographic snake, he uses Messiah Cell's body for the second season. Along with the mayor's body.
The "new" antagonists are Robo-Blaze and Robo-Roxy, based on Enter Unite and Escape Evolve. They can be blown up multiple times but keep coming back.