Quarterdeck runs in the browser with nothing to install, and almost all of it needs no account: lessons, a ship alone at sea, set battles against the game's captains, battles with other players, and Corona del Mar, an open sea of your own.
Tutorials
Short lessons at sea, with your orders shown one at a time over the water. Basic Sailing teaches the helm, the sails, the yards, the compass rose and the telescope. Basic Gunnery starts you stopped beside a target hulk, and teaches manning and loading the guns, shifting the gun crew from one side to the other, the three kinds of shot and firing at will. Start from the Tutorials page. Leave game brings you back to the list.
Sea Trial
Any ship alone in open water, with a steady breeze from the north and a Cabal hulk lying 600 metres ahead as a target. The hulk has no guns and never strikes, so you can practise on it for as long as you like. Take a frigate from the welcome page, or any ship, including the brigantine and the boats, from its page in the shipyard.
Frigate Duel
Your frigate against one Cabal frigate, captained by the game. It's the welcome page's Fight button, and the plainest test of everything in this guide.
Battle Builder
The Battle Builder sets up any battle you like, the Crown against the Cabal: up to eight ships a side, any of the five warships, each one under a player or a game captain. The two lines start abreast of each other. The page tallies each side's guns and broadside.
The battle you build is kept in the page's address, so you can save it or send it to someone. With one player the button sends you straight into the fight. With more, it opens a room for the others to join. The game's captains on your side are in your squadron from the start, under your signals: see Squadron and Signals.
Rooms
A room is a battle with other people in it. A member hosts it, from the Battle Builder, and sends the room's link to the others. In the lobby each player claims a ship, and the host starts the battle. Every ship nobody claims is sailed by a game captain. Visitors without an account can join a room as a guest, under a name like CaptNoob1234, but only a member can host one.
If you lose your connection, your ship lies idle for ten seconds and then a game captain takes it. Come back and you take command again. A room closes once it has stood empty.
Corona del Mar
The sea round Corona, yours alone. The Cabal is out there, and you see only what lies within sight of your own ships. Your chart starts blank and fills in as you explore. Members keep their voyage and their chart with their account. A visitor can sail it too: their voyage and chart are kept only in that browser until they sign in, when they join their account, and a visitor's crew is always 60. Corona del Mar is still being built.
You arrive ashore in Corona with a crew of at least 60, enough for a cutter. Before you put to sea, choose your ships: as many as your crew can man, up to two, from a cutter (60 crew) through a brig (120) and a frigate (280) to a seventy-four (600) and a first rate (850), and mark the one you command. You put off from Corona's mole in its boat, with your ships lying 100 m out: row out to the one you command and press B alongside to go aboard. The rest sail with you in squadron, and any crew you don't take waits ashore. When you come ashore, your crew is everyone still aboard your ships plus those who waited, and never less than 60. To come ashore again, sail back within 1 km of Corona and all but stop (under 1 knot), then press P or Go ashore. In a boat, the boat must be within 1 km, wherever your ship lies. If you leave while at sea, you come back where you were, with the same ships and crews.
When you put to sea a Cabal ship comes out: mostly a cutter, now and then a brig. It lies hove to south-east of Corona, within sight of the town, and your chart marks where. It lies there until one of your ships comes within 3 km of it, and then it comes for you; take it, and the next one waits. Your guns are for the Cabal alone: your shot passes through your own squadron's ships. A Cabal ship that strikes is yours to take: row across and press B alongside, if you keep fewer than two ships. Its crew joins yours. If your own ship strikes, you take to its boat with the men left; row to another of your ships, or press P to come ashore from wherever the boat is.
Engagements never end
Whichever way you play, a fight has no victory screen, no defeat and no time limit. Ships strike, prizes are taken, and the sea goes on. Leave game in the Esc menu takes you back to the site, and Fight again starts the battle over.