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The planning test neuropsychologists have used since 1982, turned into a race. Coloured balls sit on three pegs of different heights; rearrange them to match the goal in exactly the fewest possible moves. Every puzzle's minimum is computed exactly, the clock shortens with each one, and one move over par costs a life.
Two pictures are on the screen. The small one at the top is the goal; the large one below is your board. Both have three pegs of different heights, and the balls on your board have to end up arranged exactly as in the goal, with the same colours on the same pegs in the same order from bottom to top. Each ball also carries a shape, so the puzzle works without telling colours apart.
Tap a peg to lift its top ball, then tap another peg to drop it on top of whatever is there. Only the top ball of a peg can move, and a peg can never hold more balls than its height — in the first puzzles the pegs hold three, two and one. If you lift a ball and change your mind, tap the same peg again to put it back; that does not count as a move.
Every puzzle shows its par, the smallest number of moves that can possibly solve it, worked out exactly by searching every position. You have to solve it in exactly that many moves. If you reach the goal at par you score the par in points and move on. If you use up the par without reaching the goal, the puzzle is lost and so is one of your three lives.
A time bar runs down on every puzzle, and running out also costs a life. The time allowed shrinks by five percent with each new puzzle, the par climbs, and after the first stage the puzzles bring in a fourth and then a fifth ball on taller pegs. The run ends when your third life is gone, and your score is the total par of every puzzle you solved.
Work backwards from the goal. Look at the bottom ball of each goal peg first, because it has to be put in place before anything goes on top of it. The first thing to ask is which ball must land at the bottom of the tallest peg, and what is currently sitting in its way. Everything else follows from that order, and planning from the top down is the most common reason people spend one move too many.
The one-ball peg is both a parking space and a trap. It is the only spot that can hold a ball aside without burying anything, so the whole puzzle often turns on what you park there and when. But it only holds one ball, so before you drop a ball on it, check that you will not need the space again before that ball can leave.
Beware of the obvious first move. The move that puts one ball straight into its final place is often wrong, because it blocks a peg you still need to dig through. The par is exact, so if your plan needs a ball to go in and come out again it is almost certainly not the shortest route. Count your whole plan against the par before the first tap — solving it in your head is faster than solving it with your fingers.
Use the early puzzles to get fast. The clock shrinks by five percent every puzzle, so the first eight three-ball problems are where you bank time and points while the plans are short. By the time the fifth ball arrives the clock is under a third of what it was at the start, and the runs that score best are the ones that can see a ten-move plan in a few seconds.