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Each ship has 5 slots in the inventory.
Three of them can be equipped with so-called "modules", the other two are for figure heads and special skins that you can win at events.
In addition to the size of the ship, each module also has a place where it can be installed. These are called "Keel", "Bow" and "Star" in the module. This corresponds to "Head", "Torso" and "Legs" in your ship's inventory. Meaning in the overview:
Keel -> Head
Bow -> Torso
Star -> Legs
There are modules for the following bonuses:
Crew: + Crew
Durable: + Resistance
Fighter: + Damage
Glascannon: + Damage / - Resistance
Hauler: + weight (steamship only)
Ramming: +Ramming Dmg / - Damage (Trireme only)
Tank: +Resistance / - Damage
Transporter: +Weight
Modules increase in quality from fine to unique, as you are used to, and can be Grinder upgrade.
In principle, most modules fit into every ship. However, there are exceptions. The biggest exception is the weight modules. Only a weight module for the correct ship size can be installed on your ship! You can tell which ship size your module is assigned to by the label: "Small", "Medium" and "Large". For example, "Large Transporter Module".
The ships and transporter modules are assigned as follows:
Small: Dhow, Schooner, Caravel, Buss
Medium: Junk, Trireme, Red Lion, Hornet, Brigantine
Large: Carrack, Leopard, Galleon, Frigate
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