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You can find this challenge on all seas in all grids.
Your task is to defend the crate against attacking ships.
As the quality of the crate increases, so does the number of attackers, the level of the attackers and the number of rounds.
The reward is blueprints for building ships. Planks, sails, decks, but also cannons. The quality of the plumb increases with the quality of the crate.
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