Bio begin? yes that's what your species is. We are metallic Begins. we have met all kinds of begins... But unlike most metal begins we were not programed, we are more bio in personality than we are metal.
More metal-beings? We must find the factories that produce you and the Autobots and claim them. Our keen senses will find them before too long...
The autobots use the all-spark cube, machines lifeless can be reborn into a living vessel. Our gift to them was the information to replicate this technology. we ourselves reproduce through Magic... a simple forging spell that created the metal body and the Crest of Creation to bring us to life. in a way, there is no way to stop us population wise unless you kill all of us.