First of all to start Selva's guide you need to have completed several other questslines:
You'll also need some several items for the quest:
1 Hero's seal (Drops in PY/BC/ST and FF)
1 Corridor of Assize key
10 Philosopher stones
20 Wolfs meat
10 Elviots leather
1 katovic soup wich needs
-50 Wolf meat
-20 Golden Apples
Talk to the Auch Adjutant to start the quest:
She'll ask for a hero's seal to prove you're good enough for the quest first.
These drop of the bosses in Battle Colluseum, Poison Yard, Secret Temple and Faction Fight.
You'll get the follow up quest then and are asked to go to Nunez in port Coimbra, he tells you Dr Fran Mothenstein might know something more.
So now you need to go to Gehenna Bridge Jaquin prison and use the key of assize by talking to the gaurd.
If you don't see any bosses inside, you can wait for 2 hours (since that is respawn on it) or you can try another time.
After fighting with Dr Fran Mothenstein he should tell you some more about the quest and sends you to Katovic snowfield to talk to the quest guy with the red horn like hair.
He'll send you of to Frozen Waistes to kill a avalanche apparition from ryrin's heart (closeby invierno)
If somehow the spawning goes wrong it seems you can give the npc the 10 Elviot leathers and 20 wolf meat to pass this part.
The Avalanche apparition shouldn't be tough and easy to handle .
once killed if chosen the other option you should get a quest scroll.
Bring the scroll to the red horn guy and he'll send you off to invierno in frozen waistes, After talking to invierno a lvl 80 Selva attacks you, nothing tough you should even be able to afk it .
After looking at the scroll it seems to point out a certain book with information.
Off to the library to find it!
(I'm talking about torshe's mansion now just so you know :p)
Talk to Dr torshe to ask where the book is, of course he doesn't even know, so you'll need to look for it on your own.
The bookshelf on the first floor should be clickable and warp you into a instance.
Once inside you'll get to talk to cortes and he'll help you and selva with somebody that needs curing.
and here's the dreaded part we need another kato soup!
you've already gotten a soup before so i'm pretty sure you know how to make it .
Go back to the book shelve in torshe's mansion to give the soup to cortes.
Once Cured he's back to his evil self! and he'll attack you...
luckily hes rather old and fragile (55ar/dr) and doesnt pose a thread for anyone that already completed ceabolian questline.
Now go to Dr Torshe to talk to him about cortes and after that go back to the Auch Adjutant in Auch to get selva's card (and torshe gives you her special stance books after talking to him)
To see her stats and stances go to :