One colour in each level has a lit fuse attached to a move countdown. That colour must be completely sorted before the countdown reaches zero, or the level ends — the other colours have no such deadline.

The pouring rules are the same, but the fuse forces you to prioritise. In a standard water sort you can solve the board in whatever order is most convenient; here you often have to go directly for the fused colour and accept a messier board elsewhere.

Playing the level as though there were no fuse — tidying the rest of the board first and running the countdown out. Find the fused colour at the start, work out how many moves it needs, and prioritise accordingly.

Yes. Undo, Hint and Restart are all available, and you can retry any level from the level select.