Resonance Hall

You stand on a podium in a black void holding a baton, and the rule is one sentence: the hall is built out of the gestures you land. Conducting patterns arrive as glowing paths in the air ahead of you. Trace one in time and a pillar rises, an arch spans, another segment of the vault crawls further across the ceiling. Miss it and that piece of the building is simply never there.

Nothing is repairable. A gesture is scored the moment it completes, and what it builds is permanent for the rest of the piece — so a bad third minute stands in the finished hall. There is no fail state and no losing screen. A badly conducted piece leaves a ruin, and the piece ends the same way either way: with a slow orbit around whatever you made. That orbit is also the only time you see the vault: while you are conducting, the camera stays low on the podium and the vault crown is directly overhead, out of frame.

How it plays

• Three pieces — I. Foundation, II. The Span, III. Closing the Vault — four movements each, about nine minutes end to end. 54, 42 and 42 elements to build, standing on 18, 14 and 14 pillars.
• Every gesture is scored on when it completes and on how closely you traced it, folded into one number. At 0.85 and above the element finishes solid; between 0.5 and 0.85 it builds partially — a pillar at two-thirds height, an arch that does not meet; below 0.5 nothing is built and the gap stays visible. There are four gestures — downbeat, sweep, circle, hold — and the recogniser is not equally good at all four: a cleanly traced circle scores about 0.71 where the other three score 0.89 and up, so the rose windows a circle builds come in partial even when you trace it well.
• Timing is the whole game, and it is worth a measurable amount: a test hand playing to the beat scored 0.819 mean quality and built 48 of 54 elements. The same hand ignoring the beat scored 0.423 and built 8. Full timing credit lands inside ±90 ms and decays to zero by 420 ms.
• Failure cascades through the structure rather than the scoreboard: an arch needs both its pillars, the vault needs its arches. One missed pillar costs at most five elements downstream, because the rose windows alternate around the ring and a single collapse can only ever reach one of them.
• Prompts arrive no closer than about 1.9 seconds apart. Conducting is slower than tapping and the chart is written around that, not squeezed to fit it.
• A six-tap calibration measures your input latency before the first piece, and it is not optional — everything after it is judged in milliseconds.

Every surface is emissive line geometry and additive billboards over a near-black void. Nothing casts a shadow, nothing has a texture, and the only solid object in the game is the podium you are standing on.

Two things about that look are unfinished. The play-time HUD has no backing panel, so its text is drawn straight over the hall and can sit on a white-hot pillar where it is hard to read. And up close an emissive core renders white rather than its own colour, so the cyan-and-violet coding that tells an arch from a pillar survives in the halo and at hall scale but not on the pillar beside you.