Nothing supernatural at all. Razgriz was a folktale being that brought destruction in a war torn land, killing everybody and itself. Sometime later, a traveler came by the decimated land and cultivated it anew. That traveler called themselves "Razgriz". So Razgriz is both a demon of destruction and god of hope. During the events of 5, multiple things/groups got referred to as Razgriz. It eventually fell upon you and your squadron by your enemies and allies alike for first kicking ass, faking your death then coming back stronger and hard to the point of stopping a weaponized satellite with railgun and nukes and an ultrasecret Belkan (THEY DID NOTHING WRONG) organization that started the whole war in 5 (After the events of Zero where Belka started that war (THEY DID NOTHING WRONG).
I had to look that all up because even I was confused when I play it 10+ (I think...) years ago. Silly, cheesy and melodramatic, I know, but you flew through a tunnel to destroy a control center (staple of the series, for better or worse) and then shot down a falling satellite with a nuclear payload. And you get called a mythical demon god while this is playing:
At the very least in these games you'll feel like a badass. Maybe I should track down 6 to play. I didn't play that one since I didn't have a 360 for the longest time and it fell off my radar.