Besides monsters, various chests and crates may appear in the water. Collect them for extra money and to fill the chest meter on your ship, which will unlock a free spin for even more prizes. The free spin may even give you an artifact. Use the free spin as soon as it becomes available in order to allow your crate collecting to count towards the next spin.
Bosses
Boss battles eventually become very challenging. You will have to use your Captain's special skills to win. Use them a portion or all of his skills to defeat the Boss and continue. This is the only when you must use the special skills.
Crew
At first you will not have a choice over the crew you will get and their upgrades. They will be unlocked them as you earn money. Concentrate on upgrading crew members that give you better boosts (either with damage for all characters, extra money, etc.). Tap the first skill of each crew member to display all their skills to decide which ones are more valuable.
Damage
As you progress you will be able to spend progressively less time actually clicking. Instead, you will have to supervise your crew and have them make progress for you. You must upgrade your captain's DPS early when you have to do most of the tapping. Upgrade the skills occasionally, as they are very valuable during Boss fights.
Money
You will occasionally be given a chance to watch an advertising video in exchange to double the money you will earn for four hours. This offer becomes available when as an exclamation mark appears at the top-right.
