Avenger on the map.
Blue Beard's Avenger (Avenger for short) is a Privateer ship and is owned by Blue Beard. The Avenger was a ship set but was never released. However, it is on the map that comes with the primary skull sets(shown at right). The name may be a retcon pun of blackbeard's ship Queen Anne's Revenge.
The ship may be released as a 2.0 set, however, this is unlikley