How to play
- Goal
- Open or close every door so each number counts other rooms visible in straight lines, and all rooms stay connected.
- How it ends
- Every door is decided, every sight count matches and all rooms are reachable; there is no loss state.
- Record
- Each chart keeps your first solve time, and an uninterrupted first solve can claim the named fastest time.
- Each square is a room. A number counts other rooms visible north, south, east and west through consecutive Open doors. Exclude the numbered room itself.
- A Closed door stops sight. Sight cannot turn a corner, but travel through Open doors can turn.
- Every room, including blank rooms, must remain reachable from every other room through Open doors. Blank rooms have no quota but still count in sightlines.
- Decide every door as Open or Closed. Tap a room to inspect its straight sightlines and current count.
Controls
| Mouse / touch | Select Open, Closed or Erase; tap a door or drag one undoable stroke. Tap a matching mark again to erase it. |
|---|---|
| Arrows + Enter / Space | Move door focus and apply the selected tool |
| O / C / Delete | Open / close / erase the focused door |
| Z / Y / R | Undo / Redo / open Restart confirmation |
| Pan / P | Move a large chart without painting |
| Whole chart | Open a read-only overview from the chart menu |
| Escape | Cancel a stroke, close a dialog or return to the atlas |
| Controller | D-pad move; A mark; X cycle tools; shoulders Undo/Redo; B back; Start settings |
Tips for Seethrough
- Stop at the quota When a room already sees its full count, an extra Open corridor would overshoot.
- Keep a route Correct sight counts alone do not finish a chart. A blank room cannot be isolated.
- Trace straight rays Count separately in four directions. A route around a corner adds no rooms to that sightline.
Questions about this game
Do I count the numbered room itself?
No. Each number counts only other rooms.
Can sight turn at a junction?
No. Travel may turn; sight stays straight.
Do blank rooms matter?
Yes. They count when visible and must join the same connected network.
Are the shelves difficulty levels?
They describe chart sizes: eight 4×4, sixteen 5×4, twenty-four 5×5 and forty-eight 6×5. No difficulty ranking is promised.
Does Restart reset the clock?
No. It clears marks while retaining the original first-solve clock. Undo restores the cleared marks.
What happens when I replay or reload?
Completed charts open in untimed Practice and preserve their first finish. Reloaded unfinished charts retain marks and Undo, and their time stays local.
Charts and the worked example are original. Marks and Undo save in this browser. The first clock starts when a chart is selected. Reloaded attempts and detected clock or browser-suspension discontinuities stay local. Unsafe or unavailable storage is reported in-game. This is an independent implementation of the Seethrough (Doors) puzzle rules.
Watch how to play
About Seethrough
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