Find an Avenging Caitiff at -66.16, 324.82, -234.16. This is the room behind the secret wall at the back left of the Graveyard where a Deathly Herald, a Shadowy Scribe and a Deathly User lie in wait behind doors as a trap. While I do not believe that the Avenging Caitiff spawns in this room, it definately paths into here which is an advantage as you do NOT have to go through the one way door onto the stairs where it normally paths (making escape much easier).
You say, 'Hail, an avenging caitiff'
an avenging caitiff glares at you with fangs bared as he draws an electrum-bladed wakizashi.
You say, 'what electrum-bladed wakizashi?'
an avenging caitiff says 'HA! As if a mortal such as yourself is worthy of such a weapon. Leave me to my misson - my purpose in life - the slaying of those who brought me into this existence, then exiled me from this place.'
You say, 'what purpose in life?'
an avenging caitiff says 'My mission is to free those who made me what I am, avenge my exile and take revenge upon all vampires.'
You say, 'who made you?'
an avenging caitiff says 'Both of my parents are vampires. My mother was fourth generation of the Mistmoore lineage. On the night my soul returned to this realm, my mother bestowed the curse of immortality upon my father. Nine moons later, I gleaned my first vision of this world with these tainted eyes. It was not until some time later that they discovered I was different.'
You say, 'who is your mother?'
an avenging caitiff says 'My mother was named Issis. She is, to my knowledge, employed as Lord Mistmoore's maid.'
You say, 'who is your father?'
an avenging caitiff says 'Syncall is my father's name. He serves as Lord Mistmoore's butler.'
You say, 'what is different?'
an avenging caitiff says 'Since my mother was a vampire, my blood, too, was of the accursed lineage. However, the Mistmoore blood ran thin in my veins. My body was imbued with many of the attributes of a vampire but my soul was not corrupted and my will prevailed over the curse. For this, I was cast out and banished. And so, I hunt vampires. There is no more.'
Now you need to go deeper into the castle and kill Mais Issis and Butler Syncall to get their fangs. I cheated and bought them in the bazaar for 100PP each. Give the Avenging Caitiff Maid Issis Fang and Butler Syncalls Fang for the following response:
an avenging caitiff says 'Mother? Father? May you find peace at last. I shall avenge your suffering! I will grow stronger and set free the souls of the others.'
You gain experience!!
You get given an Electrum-Bladed Wakizashi .