What Roger didn't know was that the Dragonborn he thought of were merely hybrids with dragon bloodlines, whereas what was manifesting in Amanda was no longer just simple Earth Dragon bloodline.
Among Magicians, most understand Dragonborn as being much like what was present in Lancelot, but as for Amanda...
Roger didn't have a particular understanding of Magician cultivation, he only knew that Magicians fundamentally pursued spiritual cultivation while also tracing their bloodline's origin.
The previous stages were all about purifying the special bloodline one possessed. Starting from Third Tier, when they moved to Fourth Tier, they also needed to condense their own Pale Blood.
But the Pale Blood of Magicians was different from Bloodline Hunters; they needed to use the bloodline contained within them as a base, extending upwards in spirit, reaching out to connect with more powerful ancient creatures.
This was a very dangerous process.