Important hints!
Always play logged in.
Remember code in level 1. It will come in handy later.
Remember code in level 9.
Remember password "hard" in level 20.
Fun. On Google level try to search "Google" and "Kongregate". Correct search query is "Level 22"
Remember LevelHack version in level 10. You will need the string "LevelHack v1.#" later.
Password in clicking level 28 ("9617") may be universal, as hint says. Don't tried it, anyway.
Level 31 password is the "game" word.
Level 32 password is "Level". Press "Shift" to see the hint. You don't need to wait here!
Levels 36+ levels are time runs. Be careful and fast. Otherwise you'll be moved to level 30.
The passwords are: 36: "22" 37: "9" 38: "23" 39: "18" 40: "LevelHack v1.#" (insert your version number here). 41: this level is just a time waster. 42: "this" 43: Don't press the button. Mouse over hint. 44. Press the button. 45: "correct" 46: immediately press OK. Levels 48-49? WTF? 50: "Y"
Press "+" to keep this hints!
Level 12 on Admiral is a piece of cake. Just follow harvestsun's instructions, but keep in mind that after level 2 100% accuracy bonus would be better than All ammo saved bonus. So make one shot with 2-3 cannonballs - and additional money is yours!
Now let's talk about how to complete the final challenge. You see, this Big Bad Ship has one nasty ability: additional ships spawn. It doesn't count towards ship total, and appear after some part of boss total hp is gone... So let's fight him without dealing damage at all. You need save your pirates on board across all level encounters. Dodge like hell, don't let engage yourself in close combat, damage, damage, damage. Oh... and save at least 120-130 pirates for Boss. When you succeed and the boss finally appears, just let your pirates make bloody carnage on it's ship decks =))). Yes, they CAN kill 400+ enemies. YAARRRrrrrrr! Plus this to keep it on top!
 "Mighty Knight"){kind=icon}
 "Frontier"){kind=icon}
 "Level"){kind=icon}
 "Defend Your Nuts"){kind=icon}
 "Treasure of Cutlass Reef"){kind=icon}