I know this is the 2nd guide i've made today, but it cant hurt. I'm pretty good at boss battle and know alot about it, I wanted to share what I know with everyone else
Getting a crew together
-You should aim for at least lvl 30s for boss battles. The staff makes it easy, and the bosses on the pearl range from 28-36, so below 30 wont be easy.
-Call up your fellow pirates for the boss battle, whisper something simple like "Wanna do a BB?"
-Try to max the crew, it can hold up to 12
-Choose who should have the wheel, someone with all skills learned, and knows boss battle well. Lvl 40s not reccomend unless they know what they are doing.
-After crew is assembled, proceed to the next step
START THE BOSS BATTLE
-Have the person with the boss battle start it, by going to the treasure chest>lookout games>Treasure maps>recover the black pearl>Start it with your crew
-Boss battle will then begin to load. The more full the server is, the longer it will take.
-After that the video/cutscene will start.
-You can press
esc for it to skip through the video/cutscene.
Everyone must press esc for this to work!
DEFEAT THE ENEMIES
-Staff-users: Take down the navy guards by using wither and/or fire
-If you dont have a staff, stay back or heal
-After enemies are dealt with, proceed to the next step
TAKE THE WHEEL
-The mate that was decided to take the wheel, this is your que! take the wheel!
-Make sure everyone is situated and ready for battle
-Even sides out, depending on the size of the crew. (if maxed, 6 on left side, 5 on right)
-Advance up the river and proceed to the next step.
DESTROY THE NAVY SHIPS
-Everyone man the cannons!
-Take down the ships on the left first, they do more damage
-After the ones on the left are destroyed, all cannoners with fury go on the right side. If only a few have fury, lightning is great too, fury is just faster, but lightning is slightly more powerful.
-After navy ships are sunk, proceed to the next step
TAKE DOWN THE BRIDGES
Bridge #1
-Captain, decide which side you want the strong cannoners on.
-use open fire now
-use leadership
-If you are starting to take damage fast, use take cover
-After bridge is destroyed, proceed to the next bridge
-you can wait for skills to recharge, or not, depending on your crew, how much damage you have already taken, and
Bridge #2- fort #1
-Approach the fort from the right side past the destroyed bridge
-Back up untill the pearl cant back up anymore, on the right side.
-Use open fire
-fire broadsides on the only fort that can shoot at you
-Someone in crew yell "Clear" so the capt can know its good to move on
Bridge #3- fort #2
-Even out the sides, all cannos will be active on this one
-Use Leadership, and open fire. Take cover if needed
-use broadsides to help the cannon, cannons keep doing your job
-move on the final bridge
Bridge #4
-DO NOT STAY BACK, THE FURTHER BACK YOU ARE, THE MORE DAMAGE THE CANNONS WILL CAUSE-
-even out the sides, all cannons will again be active
-Approach the bridge with ramming speed!
-use all of your skills, take cover, leadership, and open fire. Broadsides when needed.
-After bridge is destroyed, advance to the Goliath!
TAKE DOWN THE GOLIATH
-All strong cannoners on the left side, non-strong cannoners, provide entertainment, flip a coin, or dance or something

There are different strategies you can use to take down the goliath, here are a few of them:
Strategy #1
-Take it on the normal way
-Use open fire and leadership
-Use take cover as soon as the goliath fires a shot
-Fire a broadside
-That should be it
Don't like this strategy? Think its too risky? take a look at the next one
Strategy #2
-Ram past it
-Use ramming speed to get past the goliath
-Use take cover if you need to
-shift the ship using the arrow keys to allign your broadsides to the ship
-Crew, finish it off!!!
Congrulations on defeating your boss battle, you deserve it, now go get your leadership from Jack Sparrow!!