Difficulty
Learning paths through this topic
Weed out puzzle solves that are too fast or too short to be real play
A few odd records can make a hard level look easy: a replay tool, a bug, or someone mashing buttons. This entry shows two cheap checks that catch most of them and keep your difficulty numbers about people actually thinking.
Is a level with a random start decided by skill or by the lucky draw?
When every attempt begins from a different random board, some starts are simply easier. This entry shows how to tell luck-driven levels from skill-driven ones by comparing how different the starts really are with how different chance alone would make them.
How many moves do players waste after the puzzle can no longer be won?
In puzzles where one wrong move can quietly ruin the board, people keep playing a lost position without knowing it. This entry shows how to measure that wasted effort and what the number says about when to warn or offer a restart.
How many levels does it take before players have really learned a new puzzle mechanic?
A mechanic that is introduced and then used right away must be learned somewhere, and the data shows where. This entry shows how to follow the same group of players through their first uses and avoid the illusion that the curve flattens by itself.
Is the target move count of my puzzle level too tight to ever reach?
Looking only at the people who finished a level makes the target look fairer than it is, because everyone who gave up is invisible. This entry shows which group to count, which two numbers to read side by side, and when to loosen the target.
Rank puzzle levels by how often they get skipped without being fooled by small numbers
A level skipped by three of three people tops any list sorted by percentage, yet tells you almost nothing. This entry shows how to rank levels so thin data cannot jump the queue ahead of levels with solid evidence.
Does my puzzle have one narrow solution that everybody must guess?
If every finisher ends with the same answer, the level may be a guessing game rather than a puzzle. This entry shows how to compare finished solutions fairly, including the trap that makes identical answers look different.
When players fail a timed level, is the clock the problem or the puzzle itself?
Both a tight clock and a hard puzzle end in a failure screen that looks the same. This entry shows the one extra number to log at the moment the time runs out so that you know which of the two to change.
Find the one move in a puzzle that most players take back
Undo presses point at the step where players realise they were led astray. But counting them the obvious way always blames the first moves of the level. This entry shows what to divide by so the real trap stands out.
Estimate how hard a word puzzle answer is before any player has seen it
When you add new answers to a word game you want a rough order of difficulty on day one. This entry shows a simple score from the letters of the answer and, more importantly, how to check it against what players do so you can fix it.
Plan a difficulty curve that climbs but gives players room to breathe
A game that gets steadily harder every level wears people out, and one that never does bores them. A good curve rises in steps with easier levels after hard ones. This entry builds such a plan as numbers you can later compare with real results.
How many sessions end in frustration, with deaths piling up before the player leaves?
A player who leaves after a calm stretch is different from one who leaves after dying again and again. This entry shows how to tell the two endings apart from your event log, and what to leave out so the share is not inflated.