Forbidden Knowledge

Forbidden Knowledge is an Act 2 side quest in Dragon Age II.

Acquisition
If Idunna was spared during Enemies Among Us, she sends a letter to Hawke at the beginning of Act 2. If she is dead, the quest is received upon finding any Evil Tome.

Maximum XP and Loot
To achieve the largest possible amount of experience as well as gaining the stat boost and Voracity, destroy all five Evil Tomes, the quest will proceed and you will be led to the last book called the Fell Grimoire. Then choose to read the Grimoire to gain the stat boost. This will let you complete the quest and gain the stat boost as well as the unique Staff.

Walkthrough
There are 5 Evil Tomes scattered throughout and around Kirkwall as well as the Fell Grimoire.

You can choose any of the following options when selecting a book (they are all mutually exclusive):


 * Destroy the book:
 * (if Merrill is already romanced or has already reached +100 friendship, she won't disapprove)
 * 750 XP (1500 XP in 1.04)


 * Read the book and accept the book's deal.
 * (This will only apply for the first book.)


 * Take the book.
 * (This will only apply for the first book.)
 * , worth US$8600.

Choosing any of these options will cause several demons and abominations to attack.

Taking or reading any of the Evil Tomes will make the quest impossible to complete.

Reading and accepting the books' deal will give you +2 attribute points, but this will only work once: subsequent books will not provide attribute bonuses.

Evil Tomes
The order in which you find the Evil Tomes is irrelevant. Upon entering an area with a tome, it will be marked on the map. Be prepared to fight shades, demons and abominations. The tomes are located:


 * In the chantry on a table near the top of the southern stairs.


 * In eastern Viscount's Keep, on a bench near the throne.


 * In the Rotting Cave, whose entrance is found at the far-eastern end of The Bone Pit at surface-level, at an otherwise dead end (see map below). A Corrupted Lyrium is also in the cave.


 * In the Abandoned Thaig, whose entrance is shown as "Recently Opened Passage" in the game, and is near Sundermount's western exit to the world map. The tome is found in the main room of the thaig, along with the Nexus Golem's wares.  There is a battle in this room before getting the tome; see abandoned thaig strategy if you have trouble.


 * In a Dank Cave, whose (unmarked) entrance is found in the north-central area of The Wounded Coast (see map below). A dragon guards the tome and a modest treasure.  There is also Raw Lyrium at the beginning of the cave.

The Fell Grimoire
The Fell Grimoire can be found in The Forgotten Lair, which is an area in Darktown near the Northwest entrance next to a barrel. It will not be unlocked until all the Evil Tomes have been destroyed.

You may come across a locked door (10 cunning, 50 XP) and will need a rogue to unlock it in the Forgotten Lair. Inside the cave, there are one (1) complex (30 cunning to detect and disarm - 150 XP) and one (1) master level traps (40 cunning to detect and disarm - 200 XP) and, also two (2) master level traps (50 cunning to detect and disarm - 250 XP/trap). Ranged attacks can draw enemies into safe areas where they can be defeated and then the traps can be disarmed.

After destroying or reading the grimoire (which will grant you +2 attribute points), you will confront Xebenkeck, a powerful desire demon. The boss will summon hordes of rage demons and abominations, as well as a revenant in the second wave. See the article on Xebenkeck for strategies to defeat them.

Result
The Fell Grimoire and Tarohne's tomes were destroyed.

Rewards

 * Exorcist achievement or trophy
 * (over) 7 on Xebenkeck
 * 1000 XP (after reading/destroying the Fell Grimoire - quest completion)
 * (optional) 750 XP/book destroyed and (about) 260 XP/demon fight (for the "other" five books)

Notable items
, looted from Xebenkeck