So yes, it creates a bubble of atmosphere around a person's head which also renders them impervious to the material all around them (eq: water). Yes, that's great, but there's so much we don't know about the capabilities of the charm:
- Is there any explanation as to how that air keeps getting replenished?
What would cause it to break?
For how long can you keep it on until you feel dizzy or exhausted or have to take it off? Or can you keep in on forever?
Can you cast it on literally anything-even an inanimate object- and make it buoyant?
Can anyone provide canon answers for this?