The more Cain studied Rune Crafting, the more he began to understand that it was the predecessor to Inscription. What the Ancients could do with their innate understanding of Magic's properties, the other species supplemented with materials of various properties.
The end effect was very similar to the Inscription Runes placed on magical weapons to give them specific sub-stats, which gave Cain a clue as to where to start in his journey to make more detailed Rune weapons.
So far the proper spacing and Geometry had eluded him, but he had a bit of knowledge on regular smithing, and he could merge with someone who had a lot of it. If he added that knowledge to what he already had, and practiced until it became his own knowledge, Cain was pretty sure that he could make Rune Weapons that were not only as versatile as any other Magical Weapon, but also scaled with the power of the user.