To my knowledge, there are no books in the game that talk about Devovorga.However, is a brief story about her origin that you can find on tibia.com:
In times long gone, when the god wars waged, an ultimate weapon was forged by the most gifted minions of the demon lords. When it came into existence, its birth cry shattered the lower layers of hell for all eternity, and with it even its own creators perished. Here it was, an abominable creature, still barely conscious and by no means at the peak of its power - an ultimate living weapon that grew stronger day by day. Only a couple of demon lords were aware of its existence. They feared the weapon's power and that it could turn against themselves one day. So they decided that the weapon could not be allowed to exist. With all their might, the demon lords came down on the creature. There was no battle, no glory, just an ambush on a confused and fearful fledgling. With gruesome rituals they tore the creature apart and hid the pieces deep in the bowels of the earth, scattered all over the Tibian lands. That what could be described as the heart and brain was buried deep beneath the area that later became known as Vengoth. And here, for aeons, the torn creature had slumbered in the depths, poisoning the land above with its dark dreams. It might have remained that way until the end of time. But it didn't. The creature is awake. It started to think. Became aware of what had happened to it. Understood what it was and that it was not even complete. And it experienced pain, the thirst for revenge and the burning heat of rage.
As for NPCs, I believe only the NPC "A Beautiful Girl" (who is Devovorga before transforming) is the one that says something about herself.
Theories:
There’s something curious that has always caught my attention about this story. On the one hand, it’s specified that Devovorga was created and destroyed during the dawn of the God Wars, which means thousands of years ago, before the creation of any human. Then, her remains were scattered across Tibia, while her heart and brain were buried in Vengoth.
Following this logic, Devovorga shouldn’t have a physical form (a body) in order to return to life and plan her revenge against the Demon Lords, since only her remains (soul and brain) are still buried in Vengoth.
Now, when Devovorga has not yet transformed, we find her as an NPC called "A Beautiful Girl."
What’s strange about this, as I mentioned earlier, is that her creation dates back to before the creation of humans. So, why would she now have the body of a woman, if such a human form didn’t exist back then?
Well, one idea that came to my mind while researching this topic was thatactually , Devovorga has acquired a body (as a tool) to be able to take a physical form and begin her transformation.
So then, to whom does that body belong?
Here we can intertwine stories and theorize about this, specifically with the story of Arthei and his brothers.
Without going too deep into this part, in summary: Arthei is a human who travels from Carlin to Yalahar in search of better opportunities, accompanied by his brothers (Marziel, Lersatio, and Boreth) and his wife Kala.
After several events that you can read about in the books inside Vengoth Castle, Arthei and his brothers become infected and begin to transform into vampires. However, Kala (Arthei’s wife) flees the place in deep sorrow when Arthei was infected.
Most likely, Kala committed suicide, which is why we can find her as a ghost (the NPC "A fading memory") in Vengoth Castle. Also, Marziel (Arthei’s brother and author of the books) also gives us a clue about this fact:
"Kala is gone!! In her sadness, and confronted with Arthei's constant rejection, she must have left the house last night. We are so worried about her... and hope so badly that she didn't decide to throw her life away as desperate as she has been."
Now, if you talk to the NPC "A Beautiful Girl" (Devovorga), she gives us a very interesting response:
Player: trapped
A Beautiful Girl: I'm trapped in this useless body. But I can feel it begin to change... finally…
This lets us understand that Devovorga’s human form is purely a tool in order to carry out her purpose. This way, everything starts to make a little more sense.
-Why did Devovorga, after being buried for thousands of years, only now (in the human era) manage to “wake up”?
-Why the detail of calling her 'A Beautiful Girl' as an initial form?
Generally, these kinds of details are not random.
So in conclusion, I think these events suggest that Kala’s body, is actually the body Devovorga, which was took as a tool in order to be reborn in a physical form and take her revenge.
Of course, this is still just my own theory and it could be wrong.
Either way, it remains an intriguing story, and perhaps there's still more hidden secrets around this plot :)
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Sources:
1. Tibia - Free Multiplayer Online Role Playing Game - News
2. Me xD
