The Hull Keeper

The Hull Keeper is an enemy encountered in Darkest Dungeon 2

Description
The Hull Keeper is an enemy in the Fisherfolk faction, found only in the Shroud. It is unique in that it is an elite enemy, replacing and upgrading the Bosun. It retains all of the regular Bosun's skills, however they are stronger, as well as having a unique move from Bosuns. Visually, it resembles a Bosun except for a vest and special hat.

Strategy
The Hull Keeper is essentially a stronger version of the Bosun, and as you'd expect, it should be dealt with in the same way as a regular Bosun, albeit with more care for their higher damage and strength. Spearfishing and Heave Ho will deal hefty damage while disrupting your party, while Sodden Rigging, if the Hull Keeper strays to the middle of the enemy ranks, will inflict heavy damage to the player through debuffs and stress. Riptide, meanwhile, will help wreck your team through excess bleed and barnacle application, as well as synergizing well with his forced movement skills.

Having a party prepared for dancing around the ranks is helpful against Hull Keepers, although moving more may aggravate the Barnacles more than you can handle. Move Resist would, of course, be helpful against them, to protect against the Heave Ho! and Spearfishing disrupting your team. Moving it is valuable if you're scared of Sodden Rigging and Riptide, by dragging it to the first rank. However, this will force it to continually use Heave Ho!, so do with that what you will.

It's generally worth it to deal with the other enemies before the Hull Keeper, as the other enemies will irritate the natural disruption ability that Hull Keeper can inflict, as well as the Hull Keeper having DBR means it will take an extra attack or DOT to kill it. Clearing out the other enemies will generally leave the Hull Keeper defenseless.

Trivia

 * The Hull Keeper is supposedly sworn enemies with the Docker due to the Docker continually breaking all of his Hulls, which Docker does due to his incredible insecurity and inability to apply Stuns.