There are several configurations that work well. All depends on what you like to do. I have different configurations for each of my pirates.
I don't use chain shot or grape shot on most of my pirates (I RARELY use them). I'll list some pros and cons below:
-Shoot - IMO a no brainer...max it - the faster you can get shots off the better
-Round shot is free and does decent damage when maxed - however, you may find only placing one point here and using the remaining 4 elsewhere is more useful.
-Fire brand isn't free but also does fairly good damage when maxed and continues to do damage after it hits
-Thunderbolt - does very nice damage and is useful for long range shots (great for SVS) - I have this maxed one one of my characters
-Explosive - does excellent damage at close range (great for SVS) - takes too long to reload and IMO is not worth placing more than 1 point in
-Fury - massive damage when maxed - if you want to sink a ship quickly...Fury will do the trick - very bright on screen when firing and more difficult to aim compared to other cannon balls - this is an SVS must have IMO
-Rapid Reload - works well.....but do you need it - optional
-Barrage - not sure if this really does much (can anyone confirm?)
-Shrapnel - not sure this does much either (can anyone confirm?)
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