Getting the Doubloons You Want
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If nothing else, remember this...
Class = WHICH doubloons you get
World = LEVEL of doubloons you get
Class = WHICH doubloons you get
World = LEVEL of doubloons you get
Whenever you open a chest with other people, you will all get identical doubloons, items, and gold amounts. There will be one doubloon to represent each person that opened the chest. That means if you want a doubloon that only another class can get, open chests with as many pirates of that class as possible. If my Musketeer wants a Jackrabbit Ju-Ju doubloon, I need to open chests with one or more Swashbucklers.
Keep in mind that there are plenty of doubloons that all classes can get. One, two, or maybe all four pirates opening a chest can get these doubloons in place of anything class-specific. It is possible to get the same doubloon multiple times with one chest.
Hunting in higher-level worlds obviously yields higher-level doubloons, for all pirates who open the chest. The level of doubloon is based on the world, so even if a level 5 character opens a chest in Aquila, they will still get high-level doubloons that be the extra push they need to get through a tough battle.