The Docks' water vessels only unlock through the missing-crew quest. Talk to Barge at the shipyard and look for his crew. His promotion makes you assistant captain and opens the gates to the vessels. The Creature from the Deep has to be beaten before you can use the submarine that reaches The Deep.

How to beat it

Know its health

It starts with 280 HP on Easy and 370 HP on Normal and Hard.

Hover over the shockwaves

Its swordfish sword throws projectiles into the air and sends shockwaves along the ground. You can hover over the shockwaves.

Slide past the charge

It charges from one side of the screen to the other. Keep moving and use your Flaming Vessels for extra damage.

Based on one source. The fight tactics come from one guide.

Beating it unlocks the Into the Deep achievement. In The Deep, Torpedoes break the underwater barriers the vessel can't get through otherwise.

Sources: Gamer Social Club 100% walkthrough, MeowDB reference, Whisper of the House walkthrough.

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