Sea battles in Rulers of the Sea are something all Captains can get engaged in. Pirates, Privateers and Navies have the prerogative to attack ships. They can only attack ships that are enemies of their nation, but in the case of Pirates, that means virtually anyone. Other Captains cannot attack a ship because their crew would simply refuse, but they are not safe from being attacked and they have to be able to defend themselves.
Pirates and Privateers can choose to hunt in groups, but the Navies can engage in full scale fleet battles with one another. Fleet battles are planned by Admiralties of warring nations. They can be agreed as a single engagement or as a series of engagements, with pre-set victory conditions such as a cease fire, surrender or giving up a port. The members of different Squadrons will be ordered to appear at the event, and success will depend on the turnout and the ability of large units of ships to operate together.
Battles can also take place by blockading ports. An Admiralty plans a blockade and orders Squadrons to be present at the target port at a specific time. The objective is to destroy the port fortress and the Squadron of ships defending the port. All enemy navy ships that are present in the port will also join in the defence. If all the port defences are defeated, a port will be blockaded for 24 hours. In this time no trade can take place and the port is also open to a siege from the Army to attempt to conquer it.
A battle at sea is a tactical fight. The strength of a ship is determined by the type and condition of the ship, the quality of the crew and weaponry, and the tactics of its Captain. There are no statistics of an enemy to be seen, recognizing the potential of an enemy is a mixture of knowledge and experience.
When approaching an enemy it is important to gain the advantage of being at the right side of the wind. In the manoeuvring Captains need to prevent being hit at the bow, or worse, at the stern, sending cannon balls on a rampage through the length of the ship. Firing cannons fast and accurately is immensely important. A ship that has half the guns, but fires at twice the rate, is of equal strength. The type of cannon and ammunition can determine the range and destructive power, influencing the tactic of a Captain. Captains give orders and crews carry them out as well as their training allows. As there is a delay between an order and an action, Captains need to anticipate the movements of their ship and predict those of their enemy.