Build some Barques and group three or four together, then fight battles with enemy ships that have low command rating admirals. Once you get a Barque Admiral up to 2-3 stars, go after the 'super' ships. Make sure the high command Admiral is in command, and that no slower ships are in the fleet. If you have some heavier, slower ships in the same sea region they should help out in the battle but won't slow you down.

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