DeCava explains that he has been building a Cochlea to replace the missing one on the Manatee, and that he needs your help collecting grubs. If you keep asking him about it, he tells you he will need 100,000 grubs. 0.01% of 100,000 is 10, so all you need to do is go over to the grub on the left side of the area (near your ship) and bring it back to him 10 times (as it will keep respawning).

When in the brotherhood area there will be odd looking bumps in the ground. After going to the second floor (the same one Bug Eye is on) you can turn left past all the gold/treasure to find 3 in a group. 2 of them you can use back and forth, and then one will have a blockage. You receive a mug later from DeCava to get him a drink. Instead, go talk to Noogie (playing the bongos) and tell him to play up tempo. Quickly use the tube beside him and run to the pool of acid (make sure you aren't too close or it's hard to lock on) and then take the mug out of your inventory and use it on the pool. You can then take the mug back to the blocked pipe, and travel back and forth in it to get the trophy.

To Gain the vote and be voted into the Brotherhood, you will need to get Bug Eye's vote. He says he'll only vote you in if you beat him in a 'Face Off', so you'll need to learn some faces.

First, go down to the second level of the Brotherhood hideout and go into the open area near the pool of bile. There should be a Figurehead between the pool of bile and the mountain of treasure which you can look at to gain an expression. Approach Noogie and Moose, and pick the 'ARRR' option to see their Pirate faces. That's around 6 new face options. You'll gain 3 new faces for seeing Bug Eye's face in round 1. (It's okay if you lose, you want that to happen so you have the opportunity to try all expressions).

Then, after retrieving another cup of bile (see Frequent Tuber for instructions), go back up to DeCava's camp. You should see him every so often put down his glasses, at which point take them fast. Combine them with your Eye of the Manatee in the inventory and then give it back to him. Now, give him the cup of bile, and get the final face. Go back and try and lose to Bug Eye a couple of times (you'll have to use at least one of the previous faces he did to lose the round), and then after beating him the trophy should pop.

After you learn how to speak manatee you will need the pipe to do so. You should be on your ship, floating above the manatee mating grounds. Jump off the gangplank and walk along the ocean ground to the left to find the manatee who had once eaten you. Take out the seahorse head you found earlier, and offer it to the manatee. It will suck you up along with it, and you will find yourself in the Brotherhood hideout again. Head over to the bongo drums, but instead of putting the flopping fish on them, try playing them 3 times. The trophy will pop shortly after.

After you pick the lock of the treasure chest in the brotherhood hideout using your hook, you'll find Murray. Take him out of your inventory (using ) and show him to Bug Eye, Noogie, Moose, Santino, Morgan, and DeCava.

Actually not a story related trophy, you have to answer every question correctly while in DeCava's cages for this. It's not too difficult, and the questions are at random, so here are the possible questions with corresponding answers:

Dead Uncle--->Jugbender
Trainer--->Dante Dragota
First Love--->Gus
Hero--->GuyBrush
Favorite Pet--->Gomez
First Ship--->Knave of Toro

Story Related, all you have to do is call a vote after you have convinced all the brotherhood members as part of the story to vote you in.

After talking for the male manatee to the Sponge Guardian, you may enter the cave and acquire the sponge. The trophy will appear.

To learn the manatee language you're going to need to play around with the locket on your ship. It'll be on a barrel behind DeCava. Make sure to have your golden monkey wrench from the treasure chest in the mating grounds. Only put Guybrush's picture over DeCava's once you have done the first two options. These are the 4 options for the locket:

Voodoo Lady---> DeCava
Voodoo Lady<--- DeCava
Voodoo Lady---> GuyBrush
Voodoo Lady<--- Guybrush

There are a lot of options for this one, so I'm just going to list them. Put every card in your inventory and then replace them as follows, there will be a cutscene for each.

Marquee-->Voodoo--->GuyBrush
Marquee--->GuyBrush-->VooDoo
Voodoo--->Guybrush-->Marquee
Voodoo-->Marquee--->GuyBrush
Guybrush-->Voodoo-->Marquee
Guybrush--->Marquee-->Voodoo

As mentioned above each will trigger a cutscene and you have to do all of them for the trophy, but to complete the segment things will play out in different orders. And don't worry if you get kicked out of the locket, you can go back in to keep trying combinations.

This is a bit of a tricky one to figure out. During the battle of DeCava's ship and yours, you need to complete a few steps. First, go to your main mast and attempt to climb it. Their cannonball will bounce back and destroy your cannon. Quickly take out the Seahorse head and place it in the cannon, and fire it at their ship. The trophy should pop as the credits begin.

For A Complete Walkthrough of the Game on GameFAQs made by user dark52, Click Here