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If the player is a [Skyrim:Vampirism|Vampire]], after arriving at the manor you will have to go and speak to the [[Skyrim:Waiter|waiter]]. After speaking one of four option, the Waiter will say 'Of course' or 'I understand.' and hand you the [[Skyrim:Dinner Menu|dinner menu]] (Version 2) and you are directed to the banquet table.
Once there you have to read the feast note [[Skyrim:Please Read Aloud|Please Read Aloud]], after doing so you are instructed to begin the feast, by drinking the blood of the already enthralled [[Skyrim:Parven|Parven]]. Only then will the waiter approach [[Skyrim:Galtius|Galtius]] and bite him from behind, killing him. After Galtius's death Parven will also terminate and the [[Skyrim:Dawnguard|Dawnguard]] enter the building and everybody will start fighting.