FLOODMARK

Every spring the river comes up over the valley. You do not stop it. You aim it.

Silt from the floodwater is the only fertility your fields will ever get. A field the water reaches gains silt and yields that much grain the same year. A field the water misses loses a point every year to exhaustion, until it is bare dirt. Reedbeds and clay pits are worse: in a year the river does not reach them, they yield nothing at all.

But everything you build hates the water. Houses, granaries, mills, bakeries and kilns are silted up for a year if the river gets to them, and lost outright in deep water.

So a perfectly walled town starves, and an unwalled one drowns. The best wall is a leaky one, and deciding where it leaks is the whole game.

The year has four steps and none of them is a timer

BUILD → CALL THE RIVER → THE HARVEST IS COUNTED → THE COUNCIL MEETS.

No clocks. No energy bar. No waiting for a barn to fill while you go and do something else. The year advances when you say so, and the pressure comes from a system you aim rather than one you wait out. A run is twelve to thirty-five years — call it ten minutes.

Four systems, and they pull against each other

• HYDROLOGY — the river rises to a crest and spreads by connectivity from the channel. Dykes raise a tile's barrier. Sluices drop it on command. Causeways raise the ground itself and cut the depth. That is your entire influence over the water.
• THE CHAIN — silt to fertility to grain to flour to bread to people to labour to everything you build next. Two tiers deep and legible all the way. No hidden multipliers.
• THE BARN — everything shares one store, and anything over the cap at harvest is lost to the river. And a flooded granary loses what was in it, so where you keep your surplus is also a flood decision.
• THE COUNCIL — at each year's end the valley learns one thing, chosen from three of sixteen, and nothing is ever offered twice.

Nobody dies and no run is ever lost

A starving year costs population and costs you rank. It never costs the run — two families always stay, and a town with an empty store can always still work the ground. There is no losing screen and no softlock: 640 solver runs never once began a year with nothing to do. Undo works for the whole build phase, every year. It autosaves at every year boundary, so you can close the tab and come back next week to the same valley.

What is in it

• A 165-tile valley, newly generated every run, with a real height profile
• Nine seamless material plates, generated by our own tool from a locked palette — no stock tiles
• Sixteen Council advances, each with a seal the game composes from the advance it stands for: a glyph, a frame order, a tally rim that literally counts, and a material palette. There is no image file behind any of them.
• Twelve things to place, every one drawn in code
• Herons, geese and townsfolk working the valley while you think
• An original score, and every sound synthesised in the browser
• No ads, no purchases, no timers, no accounts, no network calls. It runs with the WiFi off.

Free, in your browser, nothing to install.

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More free browser games from Core Systems Asset Factory: HALFLIGHT, PRISMHORN, STARCHART, BANNERET: SUCCESSION, CHARGE BARGE.

Building your own game? We also make generated art and audio packs, and tools for RPG Maker MZ, Unity, Unreal and GameMaker: csaf.itch.io