Showcase 15 · Chain reaction
Ravens, Not Sliders
Twelve keeps, four houses, one map table. Drag from one keep to another and a raven carries an offer of alliance across: the banner at the destination turns to the sender's house. Every keep that changes sides sends ravens to all of its neighbours, and some of them follow. When a seat is surrounded it falls, and with its last seat the whole house falls. Or start the simulation and watch until one house rules them all.
The live demo needs JavaScript. The image shows the map table after a chain reaction; the explanation below is readable without it.
- Ravens in flight
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- Banner changes
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- Open roads
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- Seats
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- Last chain
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- Frames/s
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- Drawing
- Canvas 2D · CPU
How it works
Every keep belongs to one of four houses, shown by colour and sigil. Roads between keeps of the same house are open and coloured, roads between rivals are closed by a barrier. The first raven delivers an offer that the destination accepts: its banner turns to the sender's house. After that no hand decides any more, only a rule: when news reaches a keep, it counts its neighbours. If at least two of them belong to another house and they outnumber the neighbours of its own house, it turns as well and sends out ravens of its own. No message persuades the four crowned seats. They only fall to a siege: when all neighbours of a seat belong to the same rival house, a ring pulses around it and a raven of that house takes it. When a house loses its last seat, its remaining keeps go over to the victor. Whoever holds all four seats has won. Every game starts with the keeps dealt out anew. Only the seats stay put; a minimum and maximum of keeps per house evens out the unequal positions of the seats. That is not perfectly fair, but every house can win. The simulation plays by the same rules: after every chain a house, drawn by its size, sends a raven to a rival and mostly takes a siege that is ready.
Whether a message fizzles out or recolours half the map depends only on where it lands. The starting map is chosen so that no keep would turn on its own, yet a single raven usually sets off a chain. Every chain is sure to end: each turn caused by news increases the number of roads between allies, and that number is bounded. Before a keep decides, it weighs the news for a moment, and every generation of the chain flies faster than the one before; the shake, the sparks and the counter are staging only and change nothing about the rule. The ravens fly in real time and their arrivals are ordered in time, so every keep decides on the news that has reached it so far. Everything is drawn with Canvas 2D in the colours of the design tokens. Without animation the whole chain runs at once and stays as a still with its flight paths. Even with a winner this is not a full strategy game: nobody plans ahead here. It is a small model of how one intervention spreads through indirect consequences until one house is left.