Storm the Coast

How it works, and what you are actually deciding

First the river. Five reaches, and rowing further is not a bonus — it is a loan against your escape. The marsh at the river mouth holds nothing and is one turn from the sea; the head of the water holds a minster and is five. Everything you row up, you row back down with the shire awake behind you.

Then the shore. Eight places, one at a time, and at each one you can take it (silver, but it costs turns and rings bells), walk past it (costs a turn, rings nothing, and you get to see what is behind it), or run for the ship (keep what you have, if you make it).

The alarm only ever goes up. When it reaches the horsemen you lose the cargo — all of it, which is what makes the last decision the hard one.

The odds are printed. The draw is not.

At every single decision the page shows you what this place is worth, what it costs in turns, how many bells it rings, where the alarm stands, how long the row home takes, and — as a percentage — your exact chance of being taken if you run right now. Nothing is hidden except two things: what the next building holds, because you have not walked up to it, and where in the stated range this particular raid's horsemen sit.

That distinction is the whole design. A gamble is made of known odds and an unknown card. It is never made of a number the game declined to show you, and “add some randomness” is the easy way to make a game like this feel tense and the dishonest one. When the raid ends, the page tells you where the horsemen actually were — so you can check that the odds you were quoted all the way through were the true ones.

Five things were measured, and two of them came back broken

Four thousand seeded raids per figure, against the rules the page actually runs.

The gamble had no gamble in it. The threshold used to be a single known number, which meant “take anything that still leaves the row home safe” was a perfect strategy — and it was never caught once in four thousand raids at any of the five reaches. Zero point zero per cent, straight down the sweep. A press-your-luck where correct arithmetic cannot lose is a sum with atmosphere. Now the threshold is drawn from a range you are shown, and there is a real curve: pure caution brings home 26.8 silver and never dies, accepting up to a one-in-five chance brings home 28.7, hunting for the big prizes brings home 29.9 and loses the raid 13% of the time, and taking everything in sight is caught 98.9% of the time for 0.3 silver.

The river was a pure tax. Every reach used to return within 5% of every other at identical variance, so rowing upstream bought nothing and no sane player would have done it. The cause was that silver-per-bell was flat across the whole table — the alarm budget, not the board, set your total. With a steep gradient instead (a cattle pen returns 0.67 silver per point of alarm; the minster returns 3.75) the reaches now run 26.8 / 29.4 / 32.8 / 37.1 / 34.0 — rising to the fourth reach and falling at the fifth. The head of the water is a genuine over-reach, not a bigger prize.

Reading the board has to beat a habit. It does: “take exactly N and then run”, tuned to its best N at each reach, trails adaptive play by 2.0 to 4.4 silver everywhere.

Walking past has to be worth something — and the first answer to this was wrong, in a way worth writing down. A hunter with a fixed threshold of 14 silver gained by skipping at the river mouth and lost by it at the fourth reach, which reads as “the option is decorative in deep water”. It is really “14 is the wrong threshold where most buildings are worth more than 14” — the measurement was grading the strategy, not the game. Asked properly, best-tuned-with against best-tuned-without, walking past is worth between +1.8 and +4.3 silver at every reach. A result that would make you delete a feature is the one to check hardest, not act on fastest.

It runs in your browser and stays there

No account, no sign-in, no network. Your raid is a short code you can share, and the link opens on what you came home with — or did not. There is no code on this page that could send anything anywhere: pages in this corner are forbidden to make requests at all, and a test enforces that rather than anybody remembering.

The river, the ship and the country inland are drawn with a 3D engine, and the ship sits as far down the water as you rowed up, so the cost of running is a distance you can see. The lights inland are the alarm — every bell wakes another one and none of them ever goes out. If your browser will not give the page a canvas, all of it is described in numbers instead and nothing about the raid changes.

Argue about it in the forum

The board’s forum has a room for this. Post what you came home with, and be told you should have run two buildings earlier.

This is fan-made, and unofficial

This is an unofficial fan game inspired by The Last Kingdom — the television series and the novels of Bernard Cornwell it is based on — naming the work, its setting and its premise under nominative fair use. It is a free, unofficial fan tribute, made for fun. It is not affiliated with, endorsed by, or connected to Carnival Film & Television, Netflix, or Bernard Cornwell and his publishers.

Nobody in this game is named and nobody in it is from anything: a river, a shore, eight buildings and a body of horsemen somewhere inland are the ordinary furniture of a ninth-century coastal raid. Every line of text here was written fresh for it. No dialogue, novel text, script text, scene, still, logo or artwork from any television series or book is reproduced anywhere in it. Iron Realms — the strategy game the rest of this site is about — is an original fantasy world with its own map, its own houses and its own art, and has no connection to the world of The Last Kingdom.

The rest of the corner

The Last Kingdom wing has Lord of Bebbanburg, Hold the Wall, Holmgang, The War for the Kingdoms, Saxon or Dane, Arseling to Ealdorman, The King’s Shadow, the trivia rounds and the character pages. The fan tributes hub has the Westeros, Supernatural, King of the Hill and Fringe wings alongside it, and the free tools that are not about anybody’s fiction. If you would rather play something with a map in it, Iron Realms is free and runs in a browser tab.