ICSS

Challenge 1

Hexaku Code Breaking.

Six puzzle sets, hidden clues, and one final answer waiting to be cracked.

Summary

Solve the puzzles, crack the code.

Challenge 1 turns the logic behind code breaking into six sets of discrete Hexaku puzzles. Every puzzle shares the same core Hexaku rules, then each set adds its own twist: thermometers, comparisons, parity clues, whisper lines, cages, and the pure Hexaku opener.

When a puzzle is solved, its central cell is revealed. Solve all six puzzles in a set and you will have six central cells to combine in the right way, crack the set code, and submit the answer. The code-breaking step is not timed, so you can take your time and enjoy the lateral leap.

Each of the 36 grid puzzles can earn up to 110 points: 100 for the solve, plus a 10 point time bonus if you finish inside the limit. Wrong answers and hints deduct points. Cracking the code for a completed set earns another 100 points, taking each set to a maximum of 760 points and the six-set total to 4560.

Once all six set codes are solved, one final code remains. Crack that for a 500 point bonus and a maximum possible score of 5060. After each set code is solved, you can submit the answer and optionally update the leaderboard for a bit of friendly competition.

New to the format? Try the practice puzzle first.

Click a cell in the grid to begin.

Meta Puzzles

Solve the set, unlock the code.

Each completed set reveals six central clues. Use those clues here to crack the set code, score the code bonus, and open the next set. The code stages are not timed.

Meta Puzzle I

Hexaku

Locked

Unlocks when all six Hexaku puzzles are complete.

Decode the six clues, put the answer together, and enter it below.

Meta Puzzle II

Thermo

Locked

Unlocks when all six Thermos puzzles are complete.

Bring the right elements together; the rest is a matter of position.

Meta Puzzle III

Compare

Locked

Unlocks when all six Compare puzzles are complete.

Read the signs, choose the right mirror, then press the six answers from greatest to least.

Meta Puzzle IV

Parity

Locked

Unlocks when all six Parity puzzles are complete.

The letters set the route, but not the message; follow the colours and listen for the signal.

Meta Puzzle V

Whisper

Locked

Unlocks when all six Whisper puzzles are complete.

Check your clues, combine each puzzle with an instruction, and enter the answer below.

Meta Puzzle VI

Cages

Locked

Unlocks when all six Cages puzzles are complete.

Complete each pair, read the letters, then take your time putting them in order.

Meta Puzzle VII

Final answer

Locked

Unlocks when the final Triominos grid is solved.

Use the solved puzzles with the final clue to find what you have been doing all along, then enter the answer below.

Leaderboard

Current standings.

Scores are ranked by total points. Progress shows the latest set code or final solve submitted.

Rank Name Score Progress Date
Martin Smith 1740 Compare code 29 July 2026
Mummy Creed 1345 Thermo code 24 July 2026
Martin B 680 Hexaku code 11 July 2026
Pravan_Patil 670 Hexaku code 12 July 2026
MAR Social Butterfly 650 Hexaku code 12 July 2026

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