Is the Prophet considered a magic being?

[Herode]

If you want to see whether a unit is magical or not, check his statistics screen. The properties of the unit are listed above the magic paths (is he/she fire resistant, prophet, pretender, diseased, stealthy, etc. ?)
Magical units display a special icon (a kind of fey).

I don't know how you could make your prophet a magic unit if his chassis do not say 'I am a magic unit'. But if you empower him with whatever path, he will be able to lead a few magical units. Not sure it's worth the price, however...