Check your story and game
Learning paths through this topic
Check that a word can be made from a rack of letters, blanks included
A word-building game must accept words the player can really spell with the tiles at hand and reject the rest, and repeated letters and joker tiles are where the simple version fails. This entry shows the counting, which tiles a joker replaces, and what that does to the score.
Some lamp-toggling boards have no solution, so check before you hand one out
In a puzzle where one tap flips a lamp and its neighbours, a random pattern is often impossible, and trial and error cannot find what is not there. This entry gives a reliable way to know in advance, and to list the exact taps when there is a way.
Pouring between tubes in a colour-sorting puzzle: how much moves and when it is won
Tipping one tube into another looks like one rule, but the amount that moves, the top colour, the free space and a pointless pour into an empty tube all matter, and a wrong win test ends the game with two tubes of the same colour. This entry settles each case.
How long does the player only read before they get to decide anything?
Even a good story loses people when pages go by with nothing to do. Measuring the length of a scene is not enough, because several short scenes in a row add up. This entry finds the longest stretch between choices and the road it lies on.
Notice when a match-three board has no move left and find a hint
After pieces fall, a board can look full of colour and still offer no swap that makes a line, and the player sits stuck with no way out. This entry shows how to detect that dead end quickly, which swaps to try, and how the same search gives a hint.
Fill a new match-three board without lines that clear by themselves
A fresh board that already contains three in a row pops before the player has done anything, and filling it again until it behaves is slow and unpredictable. This entry shows a way to fill it once, cell by cell, that never creates a line, and the case where it cannot work.
Find every row and column of three or more in a match-three board
Spotting three in a row sounds like one loop, yet boards with crossing lines, long runs and empty gaps produce double counting and missed pieces. This entry shows a scan that returns each piece once, keeps the line lengths for special rewards, and never matches empty spaces.
In a card-pair memory game, extra taps during the flip-back must be ignored
Two cards that do not match stay visible for a moment, and players keep tapping, which flips a third card, breaks the pair count or turns a card back by mistake. This entry gives the small set of rules that keeps the board correct however fast people tap.
In a mine-field puzzle the first click must never hit a mine
Placing mines at random before the first click means some players lose on move one, and moving a mine afterwards can quietly change the numbers they already see. This entry places the mines after the click, keeps the opening area clear, and explains what to do on a crowded board.
A calm scene plays the chase music because of the road the player took
Music and ambience are switched on in one scene and expected to be off in another, but the player can arrive by several roads. Then some of them hear the wrong sound. This entry finds scenes where the sound depends on the road taken.
A new run keeps a secret the player has not met again, and the story breaks
Games where the second run remembers things from the first are great, until one remembered fact depends on another that was wiped. This entry checks a keep-list against the dependencies between facts and repairs it in the direction you choose.
Does the monster hear a thrown bottle two rooms away behind a closed door?
Counting rooms between the noise and the listener gives the wrong answer as soon as doors and detours exist. A loud sound can find a quieter way around. This entry works out how loud a noise is in every room, for a fair and predictable listener.