Meet the moving chain
Aim with the pointer or Left/Right, then release on the board or use Shoot or Space to fire a seed marble into the moving chain. A shot inserts beside the marble it actually reaches. Make a connected group of at least three matching colours to clear those marbles.
Use the next colour
Check the loaded marble and next preview before firing. Swap or X exchanges them when the other colour fits a better opening. A matching colour elsewhere on the path does not count unless the inserted marble joins a contiguous group.
Keep the gate clear
The chain keeps moving while you aim. Each cleared marble earns ten points. Clear the whole chain and a new wave follows. Letting the chain reach the end gate ends the run. Pause or P freezes the path, and Resume is required after switching away.