Umibozu/Ship ghost

It is a huge mini boss mob with a pitch black color that suddenly appears in the sea at night.
As its minions, it summons a phantom-like undead mob called Funayrei from the surface of the sea to attack the player.
And it can also cause a tsunami.
However, since it does nothing else, it can be defeated by summoning a ship ghost and taking measures against the tsunami.
However, my physical strength is quite high.
If you have any good ideas, let us know in the comments.
Thank you for taking a look at my idea.