The Chart Room

Pocket Sudoku for the browser — midnight-gold chart table, three isles, a finished treasure map.

Play here: /play/chart-room/

One username: tap Sign in on the title screen. The same name you use in Plankwalk or Critical Mass carries your charts.

Finish Widow’s Wake on this device and Plankwalk will know you as Cartographer. The Chart Room stays pirate. The lab floor plan lives in Critical Mass as Protocol Charts.

Credits: charts and game design JabMed Media · map plates Grok Imagine · music beds from Plankwalk (Suno Pro @JoeyJabs22) · build Vite/TypeScript.

The game stays free. Optional studio support helps fund the next voyage.

Also free: Plankwalk (pirate hangman) and Critical Mass (science hangman).

Process notes: Building The Chart Room.

How to play

• Fill each 4×4 or 6×6 chart so every row, column, and box holds 1–4 or 1–6 with no repeats
• A finished board inks that tile of the isle map
• Daily Cipher is one shared 9×9 for the UTC day
• Spyglass reveals a safe cell · Parrot pencils notes in the selected box
• Keyboard: arrows, digits, Backspace, U undo, H hint, N notes

Voyage

• Rum Cay — four easy 4×4 charts
• Widow’s Reef — six 6×6 charts
• Black Wake — six harder 6×6 charts, the cache