pixi-reels
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How do I build the horizontal reel above the reels that shows which symbols pay this round?

It is a normal ReelSetBuilder with .orientation('horizontal'). There is no separate builder in v2 — HorizontalReelBuilder and HorizontalReel were removed, because a sideways banner is just a reel set whose strip travels along X. Use .reels(1) with .visibleCells(n) for the n symbols in the banner, register symbols and pass a ticker exactly as usual. The spin contract is unchanged: spin() returns a promise, setResult([{ visible: ids }]) takes ColumnTarget[] (one entry, since the banner is a single reel) and triggers the stop, and the promise resolves with a SpinResult. Add the built set to the stage above your main one.

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