Six mistakes that cost you tries in Chain

The rules of Chain fit in a paragraph, which is why the first week goes wrong in ways the rules allow. None of the mistakes below is illegal; the board accepts every one of them and lets you find out later. Here is each one with the puzzle it goes wrong on, what it costs, and the habit that replaces it. If the notation is new, the rules explain the board first.

Reaching for the biggest tile first

The target is usually far above the start, so the eye goes to the largest addition in the hand. On Monday 7 September the board is start 79, target 160, three moves, hand +65 −28 +55 +54 −36. The gap is 81 and +65 is the closest single tile to it, so it goes down first almost automatically.

Every chain that begins with +65 misses. +65 −28 +54 ends on 170. +65 +55 −36 ends on 163. +65 +54 −36 ends on 162. Three tries, three near misses, and none of them is the answer — the set is +54 +55 −28, and +65 is a decoy that is never in it.

That is not bad luck. The hands are generated so that every spare tile is playable and belongs to at least one chain that lands within ten of the target, which means the most tempting tile is usually the bait. What to do instead: on a hand of additions and subtractions, stop looking for the tile that gets you close and look for the subset that sums to the gap exactly. The gap here is 160 − 79 = 81, and 54 + 55 − 28 = 81. One piece of arithmetic replaces three tries.

Treating the move count as a limit instead of a rule

The pips under the board are not a budget you may come in under. They are the exact length of the chain, and hard days deal six tiles for five moves, which makes the miscount easy.

Friday 11 September: start 21, target 200, five moves, hand −37 +70 ÷3 +82 +84 +76. Play ÷3 +70 −37 +82 +76 and the running value goes 21 → 7 → 77 → 40 → 122 → 198. Two short, with a tile still in your hand — and the chain is already over. The board counted five moves, the value was not 200, so that is a try: the tiles come back, the value returns to 21, and +84 never gets played. The fix is one substitution, not one more move: ÷3 +70 −37 +84 +76 runs 21 → 7 → 77 → 40 → 124 → 200.

The rule is exact in the other direction too. Every puzzle is built so the shortest solution is exactly the number of pips, so no shorter chain reaches the target and you cannot finish early by accident. Count the pips before you plan, and check that your plan spends exactly that many tiles. On a hard day, one of the six is a spare.

Not looking at the last digit

Order and size dominate a beginner's attention, and the last digit gets ignored — even though it rules out more chains than anything else you can do in your head.

Thursday 10 September: start 36, target 117, four moves, hand ÷3 ×9 −28 +28 +31. The target ends in 7. If ×9 is the last move, the value before it must end in 3, because 3 is the only digit whose nine-times multiple ends in 7. And 117 ÷ 9 = 13, which does end in 3. The end of the puzzle is now fixed — the chain finishes 13 ×9 — and all that is left is getting from 36 to 13 in three moves: 36 − 28 = 8, 8 + 31 = 39, 39 ÷ 3 = 13. The whole chain is 36 → 8 → 39 → 13 → 117.

Without the last digit you are testing orderings by feel. With it, one glance at the target usually removes half the hand. Write the target's last digit down before you touch a tile.

Playing a division before checking it divides

÷n is refused unless the running value divides exactly, and beginners read that as "the board will stop me" rather than "I should check". The board does stop you, and the refusal costs nothing — a refused tile is not a move, the value does not change, and the line under the board says why. On Saturday 12 September, playing the biggest addition first takes 27 to 104, and ÷9 then reports: ÷9 would leave 11.56 — Chain only allows whole numbers. Nothing is lost.

The expensive version is the division that is legal and still wrong. Back on Thursday 10 September, 36 is divisible by 3 and ÷3 is right there. The board accepts it: 36 ÷ 3 = 12. It feels like progress. From 12, the rest of the hand reaches 108 (×9 −28 +28) or 111 (×9 −28 +31) — misses by 9 and by 6, close enough to keep you hunting for an order that does not exist. The tile was never wrong; the position was. ÷3 belongs on 39, not on 36.

That Saturday puzzle shows the other half of the habit: start 27, target 206, five moves, hand +64 +54 +77 ×5 +50 ÷9. The multiplier is there to make the division legal. ×5 takes 27 to 135, and 135 ÷ 9 = 15 exactly; then +64 (79), +77 (156), +50 (206). When a hand holds both a × and a ÷, assume they are a pair and work out which product the division needs.

Assuming the order does not matter

On addition-only days it genuinely does not. All six orders of +54 +55 −28 from 79 land on 160, because none of the intermediate values leaves the legal range. A week of easy puzzles teaches you that the set is everything and the order is bookkeeping — and then a multiplier arrives.

Tuesday 8 September: start 97, target 516, three moves, hand −96 ×9 ×4 +54 +56. The set is +56 ×4 −96, and exactly one of its six orders reaches 516: 97 + 56 = 153, × 4 = 612, − 96 = 516. Everything else misses. +56 −96 ×4 ends on 228, ×4 +56 −96 and ×4 −96 +56 both end on 348, −96 +56 ×4 on 228, −96 ×4 +56 on 60.

The reason is worth internalising: a multiplier multiplies everything that came before it, so an addition played before the × is worth n times its face value and the same addition played after is worth exactly itself. +56 before the ×4 is worth 224; after it, 56. So the cost of this mistake is the worst kind — you find the correct set, watch it miss, and throw the set away. When a chain containing a multiplier misses, reorder before you re-pick.

Starting over in a hurry after a reset

A full-length chain that misses resets the board, adds one to the try counter and leaves the timer running, and the instinct is to start grabbing tiles again while the annoyance is fresh. That throws away the most useful thing in the puzzle. Because every spare tile is built into a near miss, the number you landed on names the tile you got wrong: 170 instead of 160 is +65 sitting where +55 belongs, and the two differ by exactly ten; 198 instead of 200 is +82 where +84 belongs. Read the difference before you touch anything.

The second half of not panicking is knowing what is free. Undo takes back your last move — Backspace does it from the keyboard — and Reset returns the board to the start. Neither counts as a try, and neither pauses or resets the timer. A try is counted only when a chain of the full length ends on the wrong number. So when you are on the fourth pip of five and can already see you are six short, undo instead of playing the last tile. Finishing a chain you already know is wrong is the only way to spend a try on purpose.

What to check before the last tile

Four questions, in this order: does my chain use exactly the number of pips? does its last move produce the target's last digit? is every division exact at the moment I play it? and is the multiplier in the position that makes the earlier additions worth what I need? If all four hold and the chain still misses, you have the wrong set — and the size of the miss tells you which tile to swap.

The strategy guide goes further into finding the set quickly, and the FAQ covers the practical questions about tries, timing and what the site stores.