Magic is often taken for granted in games. It's just a skill you learn, to be called upon by a button press or a menu option later. Earn a new spell, equip it, then use it immediately for its effects without really thinking about how it was created.
Mages of Mystralia goes deeper. It recognizes that a young mage just learning her craft will not automatically know how to maximize the effectiveness of her spells. It breaks magic down to the most granular elements, then lets players build up from there, resulting in a wide array of possible outcomes.
Then it packages this ingenious spellcrafting engine into a decent little adventure.