Growing up as a mage was not based on some specific power calculator, it was an approximation, made from certain things one could do that lower realms couldn't do.
Today, Ezra and the rest were having a class that would explain to them how to go from realm to realm as a mage.
Teaching this class was no other than Lith, the mage of gravity. His normally cold demeanor and former show of power were enough to ensure the young mages don't even think about distracting in class.
"All of you here and now are what we call Apprentice mages, you simply know their bare minimum of magic, and as such you can't even be recognized as mages yet," Lith spoke, he walked down towards the students, passing through the gap in between the seats.
He folded his arm but with one arm underneath his chin.
"Your fireballs and lightning snakes that have you all riled up and filled with happiness about being mages are nothing but the weakest and weakest of spells.