Sufuku is a daily number-placement puzzle with a different rule from standard sudoku: a number appears as many times as its value. On the illustrated six-by-six board, each row needs one 1, two 2s and three 3s. The same requirement applies to columns and regions. Gold numbers are fixed clues, and empty cells must be filled so all three kinds of grouping satisfy their counts. The site says each published puzzle has one solution.
The rules page teaches deduction through small visual examples. A line with one gap can be completed by counting what is missing. If a line already has enough of all but one value, its remaining cells must use that value. Other examples combine row and column restrictions or identify where a region must place a repeated number. The result is a counting puzzle in which a player tracks how many instances remain, rather than assuming that every digit must occur once.
The site offers a practice game before the daily puzzle and a separate tutorial link from the rules. It describes a weekly difficulty curve from easiest on Monday to hardest on Sunday, with larger boards using larger values. The daily page provides the puzzle number and date, helping distinguish the current challenge from practice. Players can review the full rules and FAQ before starting. The appeal is a compact recurring logic exercise with familiar grid constraints but an unfamiliar repetition rule, not a speed test or a claim to improve intelligence.
