The Assault on Raedric's Castle became super Derp.

[redviiper]

It began with a full out assault on the castle, as we charge through the front door. From there went into the sanctuary where we laid waste to everything in sight with the exception of this lone priest Nedmar who offers to take me to the Raedric, assuming I rescue Giacco. From that point it really got derp. In order to rescue Giacco, I end up breaking the lock on the door that Nedmar was going to give me the key for. From there I pop up in the Throne room with Raedric, whom I decide not to kill at the moment in order to save Giacco. Well I explore the top level until I find the stairs to the dungeon from there I find Giacco and break the lock on his cell, and he asks about this person Osrya, whom I surprisingly never  actually find. Then I go back up to tell Nedmar in order to tell him I saved Giacco. He tells me thank you, and then provides me with a key to the door I already broke into, and tells me good luck. 

[dukefx]

Osrya is in the very same dungeon. She's an animancer who offers another way in if you agree to kill Nedmar.

I went through the dungeon, not the front door and rescued Giacco even before talking to the priest. Neither Osrya, nor Nedmar are important, they both offer another route to Raedric.