A new race: Vampires.

Well, in that case, dragons can learn too, as they live a long time, and Archangels will go to heaven and improve themselves as much as they want, so vampires will still be weaker.

Yes, but Vampires are not limited in the spells they can learn and their knowledge.
And Archangels can only learn spells related to light, and Archdevils only to darkness. Vampires, although they were placed in Necropolis, are neutral creatures by their nature and can learn any kind of magic, so in the end, Archangels and Archdevils are doomed. And dragons can't even cast spells, they can only pump up their muscles!:D