Captain Avidius is a Redguard captain of The Katariah.
Location[]
He can be found inside the captain's cabin of his ship during the quest "Hail Sithis!."
Interactions[]
Hail Sithis![]
During the quest, Captain Avidius is aboard The Katariah and is one of the Emperor's guards along with Salvarus. They are at different quarters of the ship. Both of them can be killed and looted, providing the Katariah Master Key which unlocks the Emperor's Quarters.