In the final part of the Game , there is an battle within Pearl & Dutchman.. Callipso goes beserk and becomes Goddess and attacks the crew of Dutchman. In this part you are Elizabeth Swann withing through Dutchman Crew and Helping your Crew.. In this part you can get on the Dutchman. While you are on Dutchman , Callipso throws lighthing and tornado. To avoid getting killed by it (tornado) , you need to look around. Be on the right of ship , you will see little air. When you see where it come trough avoid being there. Example:

I'm on right and bottom of the ship. A little air comes. So I need to avoid being on bottom and I need to go upper.

After killing Jones , You will start fighting with Lord Cutler Beckett. Like in the Pearl vs Dutchman or Sea Battle , you need to get cover. To get cover , be behind the boxes with orange color on their front.. And then take a shot to the Beckett's ship and take him to your ship. He has 3 health. So throw one bomb , and he will run to his ship. Using this formula , over and over. Will make you win this Part of the game and game will be complete!