(DnD) Magical Essence

Magical Essence Basics
Magical Essence is what every human or animal needs to cast spells. Without Magical Essence (Or ME for short) magic would not work.

How to get more Magical Essence
The basic way to get a higher maximum ME is by learning and casting spells. When ever you learn a magical spell by unlocking a spec, discovering a scroll, or by being taught you will gain more maximum ME. You gain more the harder the spell is. To the DM's decision once you have cast the same spell enough times (or maybe by getting a few Nat 20s) you will gain essence. The amount of ME gained is determined by the spell and by the DM.
 * Arcane Novice: +1 ME
 * Apprentice: +2 ME
 * Proficent:  +3 ME
 * Specialist: +4 ME
 * Arcane Master:  +5 ME

A more advanced way of gaining ME is by practicing. You can practice your Arcane arts while camped. Certain specs will help with controlling your magic while practicing and to help you gain ME faster.