Originally (And Cortez also used it) I was constructing some Falconets in the lower enemy base, but this was just taking too long to do. Then I found out you can already destroy the Command Post with your existing units, the newly acquired Mortar (This was necessary otherwise I couldn't get the Command Post destroyed), and an additional ship. I also use those fishboats as decoy so my other 2 ships can survive and keep on attacking the Command Post. I'm killing those Black Bears (The Treasure Guardians at the bottom) for a bit of extra XP to get the Falconet shipment faster though it didn't really affect much :) But hey, it keeps the ship busy. "Fun fact", I used Amelia Black's special attack but apparently (And I didn't notice it in the run) she didn't use it most likely because the enemy unit got killed..