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Board.game Original

Firefly

Original · a hidden-movement duel for two

2 players10–15 minCompetitiveLight

One light hiding in a night meadow, and every answer it gives goes stale.

PlayPlayable

Ready to play now.

A demonstration of Firefly, played by the computer against itself.

Firefly — playing itself

Ways to play

  • Alone, against the computer

    Your own pace, no arranging anything. Take a move back whenever you like.

    4 opponents, weakest first
    • The DreamerSweeps anywhere and flits anywhere, by the seed. 12.3 sweeps an inning, and 150 of 250 lights simply outlived it — the meadow is very dark to a random net.
    • The PatrollerThe recency habit: the nearest square to its last sweep that the information set still allows. Cheap, and it works — 126–67 over the Dreamer with 57 dusks tied, 10.3 sweeps an inning. It hides by running from the net.
    • The TriangulatorThe heart of the information set — the square that minimises the total distance to every candidate, so the answer tells it something wherever the light actually is. 91–58 over the Patroller with 101 dusks tied, 9.7 sweeps an inning. It hides along the rim, where a catcher has fewer directions to corner from.
    • The NighthawkOne step of real lookahead through the same filter: for every square it could sweep it buckets the candidates by the answer they would give, flits each bucket forward to see how large a set that answer would leave, and sweeps the square with the smallest expected set — counting a catch as a set of nothing. 160–28 over the Triangulator, 7.7 sweeps an inning, and only 45 of 250 lights get away from it. Hiding, it reads that filter back and flits into the fattest bucket of the sweep it expects next.
    Play alone

  • Together, in the same room

    2 players. One device goes round the table, or everybody plays off the same screen.

    Play in the same room

  • Online, at a table

    A room code, joinable from anywhere. Pause tonight and pick it up next week from your device.

    Play online

About

A five-by-five meadow at dusk, and one firefly on a secret square. Sweep a square and the light answers with its DISTANCE — "the glow is two away" — then flits to a neighbouring square, any of the eight, and never holds still. Catch it in fourteen sweeps or the light is out at fifteen. Two innings, each player hiding once and sweeping once, and both innings run the same way round; the lower count takes the jar. Every answer is at least one flit out of date the moment it is given, so the whole hunt is triangulation against a target that has already moved.

How it feels

  • A glow one answer out of date
  • Cornering the rim of the meadow
  • Fourteen sweeps, then dark

What the design is for

  • The answer is a ring

    A sweep never names a square — it names a DISTANCE, and a distance is the ring of squares at that many king-steps from your sweep. One answer rules out most of the meadow; three good ones corner it; and the catcher who forgets the light moves between them is chasing a ghost.

  • The light never holds still

    After every answer the firefly flits — one square, any of the eight neighbours, standing still not allowed. Every past answer goes one step stale per turn, which is the engine of the whole hunt: information decays exactly as fast as you can gather it.

  • Two innings, one jar, run the same way round

    Each player hides once and sweeps once. The count is the game: fewer sweeps to catch, and an inning that outlives fourteen costs fifteen. When both lights escape the jar ties, and on this meadow that happens often enough to be a plan. The two innings used to differ: the second hider was made to flit before any sweep had been made and the first was not, so one light had already moved once for nothing. They are symmetric now, and a test holds them that way.

  • The hider sees, the sweeper reads

    The hider watches their own glow move and knows everything; the sweeper sees only the marks and answers on the board. The view carries the firefly for the hider alone, and the projection test keeps failing the day that leaks.

  • Taught sweep by sweep

    Six steps: the sweep, the ring, the flit, the catch, the count — and then the whole meadow to yourself. Three of those poses used to show something other than what their text said, including a "catch" step that answered three away from a light that was supposed to be under your hand; every pose is read back by a test now.

Best at
2
Kind
Mystery
Table
Competitive
Studio
Board.game Originals

The opponents

  1. The Dreamer

    Sweeps anywhere and flits anywhere, by the seed. 12.3 sweeps an inning, and 150 of 250 lights simply outlived it — the meadow is very dark to a random net.

  2. The Patroller

    The recency habit: the nearest square to its last sweep that the information set still allows. Cheap, and it works — 126–67 over the Dreamer with 57 dusks tied, 10.3 sweeps an inning. It hides by running from the net.

  3. The Triangulator

    The heart of the information set — the square that minimises the total distance to every candidate, so the answer tells it something wherever the light actually is. 91–58 over the Patroller with 101 dusks tied, 9.7 sweeps an inning. It hides along the rim, where a catcher has fewer directions to corner from.

  4. The Nighthawk

    One step of real lookahead through the same filter: for every square it could sweep it buckets the candidates by the answer they would give, flits each bucket forward to see how large a set that answer would leave, and sweeps the square with the smallest expected set — counting a catch as a set of nothing. 160–28 over the Triangulator, 7.7 sweeps an inning, and only 45 of 250 lights get away from it. Hiding, it reads that filter back and flits into the fattest bucket of the sweep it expects next.

Achievements

0 of 5 earned

  • The Jar Is Yours

    Win a dusk of Firefly.

  • Quick Jar

    Catch the light in three sweeps or fewer.

  • First Light

    Catch on the very first sweep of an inning.

  • Outlived the Hunt

    Hide an inning to the full fourteen sweeps.

  • Not a Single One

    Win while the rival light escaped.

Key art

Key art — Board.game art system

Firefly — key still
Firefly — key cover
Firefly — key backdrop

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