Whilst shape shifting itself is impossible, it is not impossible to create illusions to make people believe that you have shape shifted, although this is a very advanced technique and i have never heard of someone pulling off such a feat on multiple people for any prolonged time.
Physically speaking, magic cannot change your form ie. it cannot change you into a vampire, demon, or an animal etc.
But I have heard of people mention shape shifting in the astral plane and other planes, however I`m not that familiar with astral projection.
Aye, it is something you would think plenty of people would pick up on around beginning to learn about actual magic, yet there is always at least one person who has to ask. lol. Not a bad thing they ask, it's just by now, the subject has worn itself thin, you know?
I don't think shape shifting is even possible, our DNA can't change because you do a spell. whether the spell was well thought our or some notebook scribble made into a spell, it's just not feasible.
Okay I haven't worked with magic that long. But I have always lived in a state of constant learning. I never let my mind set limits for my body. This out look served me well through my time in the army, at work, and just about every other aspect of my life. Magic is real and is teached subconsciously through Many avenues. Look at the bible when Jesus told his desiples that if they had the faith of a mustard seed they could tell a mountain to move and it would obey. Not faith in him. Not faith in God. But faith in your faith that your request will be fulfilled. I refuse to set limits. But there might be other ways. Do you want to actually change you form or just how people see you. Gender change and things like this if possible I never seen or learned any way to do. But I have read how people change others perception on what there seeing. Any way I hope this helps.
