@MadKatzAuras a are a representation of one's power of the soul. Starting characters don't even have enough power to passively generate a detectable aura, let alone manipulate it. Also, the extent of manipulation is pretty much hiding it, changing it's psychological effect and focusing it to act as a barrier. Mostly, anyway. In RPG terms, the power of your aura is your "level". And you all start at "level" 1. You could change your skills into magic, and it could work, I guess.
@SPAssembleThat will provide problems, as mage group at start will be employed by Los Vengadores, the very same group that knights will investigate and fight.
@LeolycanLuminosity can take ANY shape, it just cannot change it's #1 property which is destroying magic. Initially, it will also always look like a brilliant white light. It can be shaped into a lightning bolt, into a pattern of flame, but it will remain what it is. A full body shroud is more than fine, but maintaining a full power, full body shroud like that will be quite draining for a new character.
Alright I'm off to work in an hour. I'll review Leo's character after I get back.