Quote Originally Posted by Morty View Post
The lack of sword-wielding armour-clad gentlemen was certainly a good part of Sunken King. The Fume Knight seems to be tough in general; I've been trying to help people fight him without any success for a while now.
That's something of the secret to the Fume Knight. Like some of the bosses in the DLCs he scales up massively in co-op, to the point where you're usually better off fighting him solo. He also has a weird aggro mechanic (ignores redeye ring, auto-aggros anyone who tries to heal) which can mess with players used to being able to relying on another player drawing attention so they can back off and heal.