Story Related and cannot be missed.
After murdering the scared and quite frankly rather understandably annoyed first boss, you'll have to go to your ship. Go there and follow the conversation, as the cutscene loads on the open sea, the trophy will unlock.
Extreme difficultyTo destroy the boss quickly, choose Technician at the character screen, along with Accuracy and Science.
Then follow the Firearms skills along as you level up in the skilltree.
Save as many bullets as you can. And use them all up. DO NOT TRY TO PARRY, just use the dodge button (
) and keep a safe distance that is just on the edge of your pistol range.
When you run out of ammo, use
to use your fury attacks and finish it off with a few well placed quick attacks.