Looks like some kind of anti-radiation armour.
Viewing post in Soulless II - The Armour Of Gods (C64) comments
From what I'm seeing on the demo GIFs, it's actually a power armor.
Personally, I think it would have been more impactful to not reveal this plot twist in the store page, but eh, minutiae. Game still looks awesome, and when I have cash to spare, I'll surely buy it.
EDIT: I have just realized what you were talking about, LOL. I should play Sacred Armor of Antiriad sometime.