The Core was formed by Amphibia's greatest minds. As Andrias so proudly stated his ancestors were glorious conquerors. Meaning they most likely wanted a type of let's say super computer to help them conquer world's, something that always thinks ahead and strategies. These great minds probably volunteered and the only thing they've ever known is we'll conquering. Then this being comes to life with it on it's mind and is secured in a basement surrounded by others who only know conqeroring and a newt who craves revenge for 1,000 years. However, Marcy has just joined the party a being who knows more then just world domination.
This theory sorta plays into the while trying to debunk the prophecy Andrias unknowingly fuels it. Plus the theory that Anne and Marcy got switched, perhaps Anne was suppose to be wit and Marcy heart considering the first temples line "keeper of the box." Meaning that while giving his robo lord a host Andrias also gave it a heart. Which could spell doom for Andrias plans.
Not sure how well this theory holds up especially considering that the Core is looking to be the big bad, but this show loves to throw curve balls. For all we know Core is a red herring and Mother of Olms is the bad guy(I still want Andrias taken down). We'll just have to wait and see hopefully not too long.
But it's just a theory, a Amphibia theory!