Flying Dutchman

The Flying Dutchman is a boss in the Pirate Invasion. It has four cannons that drop cannonballs to attack and it will occasionally spawn standard enemies that you'd find in the Pirate Invasion. The Flying Dutchman does not disappear after the Pirate Invasion is over (though it will explode if it has not been engaged before the invasion ends), and defeating the Flying Dutchman will not end the invasion. The Flying Dutchman can only be destroyed by breaking all four cannons.

Furthermore The Flying Dutchman can appear several times during a Pirate Invasion, even after being killed.

Trivia
In real life, during the 17th century, the Flying Dutchman was a mythical ghost ship that would float above the ocean. Seeing the Flying Dutchman was regarded as an omen of doom.

History
Hollandais Volant