Is Morgan being groomed into a sword?
Might sound a bit weird but from what we've seen of Morgan's abilities, from her sharpening, toughness and even her ability to incorporate enchantments within herself, they basically make her into a human weapon.
So the idea is, what if her saint transformation ability is to literally become a living sword, a bit like the Quiet Dancer is?
That would make a lot of sense given her aspect and relationship to her father, the King of Swords.
In that case, she would sort of become the ultimate sword for Anvil to wield, in fact it could be his way to get a sword that can scale up to godhood, just like what Sunny is trying to make for Nephis using a different path.
That being said, Anvil could also just kill her to get a human Echo, we already know Valor doesn't shy of using those, but that would kind of a waste.