Here is the full list of all 18 Choice of the Pirate achievements.
Steer the Crown in the wrong direction.
Steal from the Pirate King! You've got guts, Captain.
Rescue a mermaid.
Convince Evan Lark to open up to you.
Will those mutineers get what's coming to them?
Become a spy for the Crown.
Turn over your first bounty to the Crown.
Become the Pirate King.
Defeat the ghost ship.
Acquire three ships to launch your fleet.
Acquire two ships to launch your fleet.
Save Jim the Cabin Boy from an untimely death.
Defeat the Lusca.
Fall under the curse of the ghost ship. Congratulations on your zombification!
Earn the notice of El Sabio.
Capture your first target without sinking it.
Acquire one ship to launch your fleet.
Remove the threat of Blackguard from your future.