You've captured my interest. I've a student in mind!

A set of questions, though:
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[*]You have illustrated rather clear cut risks/prices involved with the over-utilization of a magic source, is learning how to efficiently draw on energy so as to delay/mitigate the consequences part of the curriculum? Rather, the over-usage of Xi can cause heart-attacks and full body paralysis, but would sufficient training mean that a magician can use progressively greater Xi based spells, with significantly less risk? Or do Magicians have set potentials where they'll have to do as much as they can with whatever amount of energy they have?[/*]
[*]Does magical energy in enough (or any) quantity have tangible form/affect their surroundings? For example, does a powerful Xi user have a visible aura, or a Sakra user of particular acuity unconsciously emit a sort of mental pressure/burden upon those around them? Would places with high amounts of Karma would have strange effects on the flora and fauna? I figure a place saturated in Mana would look incomprehensible, though, being a point where energy dies and is reborn.

Ultimately, I'm asking if it's possibly like Rukh of the Magi series of Manga/Anime, where magical energy (it's more like Life Energy) takes the form of butterflies made of light, where only those with Magical Prowess can see them unless they're gathered in rather extreme amounts. [/*]
[*]Slightly less complicated, can the energies be mixed to gain varied results? (I am really avoiding a "Will it blend?" joke, here.)[/*]
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