And this is another theory thats been in the back of my head...

Sera. (Sorry if Im going slightly off topic here)

Sera is another one who intrigues me. I definitely think there is something more to her. But I'm leaning more towards she's the vessel of andruil. I don’t think Sera knows what is going on. She seems to be hiding from memories, wants to ask Leliana about prescient visions (written in the book near her door), fears her dreams could be real (comes up in the romance), and is antagonistic toward the elven 'gods.‘ At times she seems to want the Inquisitor to reassure her that the elven 'gods' aren’t real (her reaction after returning from the Well of Sorrows <– more on her extreme feelings for Mythal in a moment).

Cole tells Sera, "there are songs in every part of you… waiting for you to hear them“ and ”the sky wants to say something, it’s trying,“ plus, Sera experiences déjà vu (Cole says it’s memories slipping to her across the Veil) and hears whispers that other elves do not (sounds similar to the mostly unintelligible whispers the Inquisitor hears if she drinks from the Well).  Flemeth has accepted and integrated Mythal (”she is a part of me, no more separate than your heart from your chest“) so she can fully understand the knowledge, memories, and power that comes from Mythal, but Sera might be scared and angry because she’s trying to suppress or avoid these feelings and the wisp is probably still too weak to manifest more strongly.

So here's the big question: if Sera contains the wisp of an ancient elf 'god,’ then why is she so hateful toward 'elfy’ elves? (elfy is an important distinction because she seems to judge people for how they act and not simply what they are) There are a few possibilities.  If Sera is getting memories from Andruil’s wisp she could be reacting to Andruil owning slaves and slaves’ horrible treatment at the hands of their elven masters in general.  She could have some understanding of the truth about the ancient elves and the atrocities committed by the 'gods,’ so she’d be angry at anyone who worshiped and glorified them.  On top of this, she can’t even explain it to anyone because she’d have to reveal (and admit to herself) what’s inside of her.  Lastly, her rage against elfy elves could be so extreme because of self-hate and guilt if the wisp inside of her embodies everything she thinks is wrong with the world. 

When you take Sera to The Fade and go to the area with the gravestones Sera’s specifically says that her greatest fear is The Nothing, which is strange unless you consider that The Nothing could be another way to describe The Void. 

Before we leave this codex behind, take one last look at the overall story of Mythal luring Andruil into a ambush and their fight that ends in Mythal stealing her strength and knowledge.  In her companion quest, Sera is lured into an ambush by a nobleman and, if certain options are chosen, she goes out of her mind with rage and wrecks him.  Her reaction was unnervingly brutal and felt extreme even in those circumstances, but it could’ve been an echo of Andruil's rage in the same way that Flemeth is still angry and wants revenge for being betrayed personally and for Mythal being betrayed in the past.  

Now let’s see how Sera’s tarot card, the "grains of light” text, and Andruil's vallaslin come crashing together with surprising clarity. 

We can usually only guess at which vallaslin goes with which elven 'god,’ but Andruil's is pretty obvious considering it’s a bow and arrow.  Now flip the vallaslin upside down and you get the layout of Sera’s second tarot card: her bow, arrow, head, shoulder and chest armor, legs, gap between thighs, and even the shape of her hair and pointed finger are all represented.  

Now compare Sera’s tarot card to the text from the ToM: whole stars appear at the top of the card and streaks of light clearly center on a glowing arrow with a pale golden shaft. 

The stars, grains of light, glowing spear (a projectile, just like an arrow), and Andruil's vallaslin are so clearly depicted in Sera’s very deliberate pose on her tarot card that it’s hard to believe this was anything but intentional.

I get way too into this lore stuff. I'm all about it.