Honor and Treachery | Act V Dragon's Dogma Guide
Last update: 11 May 2016
In short: You get a call from the south. In fact, it's a ruse of the cultists.
Difficulty level: Hard. Make sure to arm yourself with potions and a Secret Softener before encountering the Cockatrice.
At the beginning of the quest, Aldous will receive a message from the south requesting help. Before you go, stock up on potions counteracting the effects petrification (Secret Softener).
Go south to the Waycastle.
The moment you step on the bridge leading to the Waycastle it will be revealed that the whole thing was a ruse. You need to quickly go back to Gran Soren.
On your way back you'll see that the city is on fire. Go to the west gate (the south one is blocked).
Inside, a Cockatrice is raging. To defeat it, proceed similarly as with the Griffin, but watch out for one crucial element: the Cockatrice releases a petrifying cloud that can turn you in stone. The process takes a couple of seconds, but if not stopped, it will kill your character. You can counteract it with a Secret Softener and other potions (you get them from a guard in front of the gate).
Afterwards, talk to the guard waiting for you.