I used to think Mythal’s vallaslin were the branches of a leafless tree, but after seeing those lyrium veins in the Bastion of the Pure and all the lore surrounding Mythal and the Titans in Trespasser, I actually think they might be based on lyrium instead.
This sort of supports the theory that perhaps the reason the markings are called vallaslin (“blood writing”) is because they were originally made with lyrium. And perhaps they weren’t simply decorative but something more – like Fenris’ tattoos. It would not be the first or last time Tevinter “borrowed” knowledge from the ancient elves.
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This would also not be the first time that Mythal’s powers or symbols have some connection to things below the surface. I originally thought Solas’ new ability to turn people to stone was just something any mage with sufficient power could do. But then I saw someone point out that perhaps this was an intentional choice on the part of the writers – to connect Mythal and the earth/the Stone. If Mythal’s markings are actually modelled after raw lyrium, I am getting the sense that there’s even more to Mythal’s connection to the dwarves/the Stone than we currently know - beyond killing Titans, beyond warring with the dwarves.
