A long train of coloured balls crawls along a winding track toward the skull, fire your own balls into the line and burst groups of three before it reaches the end.
From a launcher in the middle, you shoot coloured balls into a chain that snakes steadily toward the hole. Land a ball so it forms a run of three or more of one colour and that group pops, shortening the train. Closing gaps can set off chain combos. Clear the whole train before it reaches the skull. Each level reshapes the track into a new layout.
Coilshot revisits Zuma, released by PopCap in 2003, which took the old marble-shooter idea and wound it into a spiral. A stone frog at the centre spits coloured balls at a train of marbles crawling steadily toward a hole in the floor; three of a kind vanish and the line snaps shut behind them.
Because the track curves back over itself, the shot you want is often hidden behind the shot you have, and the frog holds only two balls at a time. Much of the skill is in deliberately wasting one — firing a ball somewhere harmless to bring up the colour you actually need, and judging whether the line will reach the hole before you get another chance.
Coilshot is an original free browser game in the chain-matching marble-shooter tradition, with reshaping tracks, a split-wall interrupt and three difficulties. No install required.