Beacon Lattice
Cover every cell. Overlap nothing.
Every cell must be covered exactly once by chosen beacons — exact-cover logic, untimed, with progress kept locally in nocharge:pref:beacon-lattice-progress.
Reviewed collection
Logic & Number
Quiet logic and number puzzles: exact coverage, clues, digit rules, and tidy merges — none timed.
Reviewed
Inclusion method
Include a current game when its core loop is a deduction or mathematics puzzle (placement, clue solving, digit rules, or numeric merge) with no reaction-time requirement and no timer, or with a documented untimed mode.
This collection groups NoCharge’s quiet logic and number puzzles. These are not “brain training”; they are deduction and arrangement games with clear rules, no countdown, and documented keyboard paths.
Why this collection exists
The Arcade mixes reflex games, words, cards, and logic. This collection answers a specific need: “I want to think, not react.” Each member’s complete play loop is deduction or number work, and every member is untimed by default.
How we decide inclusion
A game qualifies when all of the following hold:
- The core loop is a deduction or mathematics puzzle: placement, clues, digit rules, or numeric merges.
- It does not require reaction speed; no member is timed by default.
- Its rules and difficulty labels explain their meaning (for example, Mini Sudoku difficulty = given-cell count, not a validated IQ claim).
Color Flip is excluded despite its puzzle feel because its visual mode is reaction-based (its turn-based mode lives in the untimed collection instead). Word games, card games, and Pass & Play titles have their own collections.
What you will find in the grid
Each card shows the genre, session length, and a reason tied to its rules. For example, Beacon Lattice stores progress locally while Twenty Forty-Eight only keeps the best tile reached. Neither count claims cognitive benefit; difficulty is game-specific and explained in each guide.
Limits
- Difficulty varies by puzzle; no member claims objective “grade levels”.
- Session lengths are estimates for typical play, not timers.
- Local storage is per browser and per device; there is no sync.
Related reading
- How exact coverage works in Beacon Lattice
- Nonogram: clues and accessibility
- Mini Sudoku on NoCharge: a quiet 6×6
- Registry facts
Related collections
- Untimed or reduced pressure
- Originals only
- Browser games without accounts
Why each game is included
Play →
Nonogram
Follow the clues. Reveal the picture.
Row and column runs force cells into filled or empty states by deduction; the puzzle is untimed and difficulty is described by size and clue density.
Mini Sudoku 6×6
A small grid, a quiet puzzle.
Digits 1–6 appear once per row, column, and 3×2 box; pencil marks support deduction and there is no timer. Difficulty is honestly described by given-cell count.
Twenty Forty-Eight
Slide tiles. Merge doubles.
Sliding and merging powers of two uses planning, not reflexes; the board is untimed and the best tile reached stays local under nocharge:2048:best-tile.
Minesweeper
Clear the field, one safe cell at a time.
Deduction from numbers and flag counting on 9×9, 16×16, or 16×30 boards with no reaction-time requirement.
Lights Out
Turn every light off with five-cell toggles.
Pressing toggles an orthogonal cross of five cells, so every board is a small deduction over the grid.
Sudoku 9×9
The full grid, at your own pace.
A 9×9 digit placement puzzle with verified uniqueness; givens counts (42/34/28) are the honest difficulty labels.