UNSEEN — Vision-Cone Puzzle on a Collapsing Grid

What is UNSEEN — Vision-Cone Puzzle on a Collapsing Grid

UNSEEN gives you one power and one problem. You see a ninety-degree cone, seven tiles deep, and nothing inside it can move. Everything outside acts the moment your tick ends. A step, a turn with Q or E, a wait, even a bump into a wall: each costs one tick and redraws the cone somewhere new. The tile you stand on is never observed, so whatever sits under your feet always acts. There is no timer here and no test of reflexes. The board waits for you, and the only pressure is the tick counter climbing towards the level's par.

Six things live in that dark. Stalkers step towards you whenever their tile is unwatched and freeze while you look at them. Phase gates are solid energy when observed and empty air when ignored. Drift platforms glide along a marked path and ferry you over pits, because you never watch the ground under your own feet. Mimic crates split in two the instant they leave the cone. Memory walls lose a point per unobserved tick, dissolve at zero, and block your line of sight while alive. Plates and locks close the set: a sealed door opens only when every plate is held down.

How to play

1. Move with the arrows, with WASD or with a swipe on the board; you always turn to face where you walk, which redraws the cone before the world reacts.
2. Press Q or E to rotate ninety degrees on the spot, space to wait. Both cost a tick and let the unwatched half of the board act.
3. Reach the white exit portal. Landing on it resolves at once, before stalkers, platforms and crates play, so the winning step is never interrupted.
4. Undo with Z and restart with R as often as you like; neither costs points. Three stars need a solve at or under the par shown beside the tick counter.

Strategies that work

• Rotating with Q or E buys ninety degrees for one tick, but walking into a wall costs the same tick and leaves you facing any of the four directions. To look behind you, bump the wall at your back instead of pressing E twice. On a tight par, that tick is the third star.
• A phase gate is tested against the cone you had before the step, not after. Stand beside it looking elsewhere, then press its direction: you turn and cross in one tick. Look at it first and you burn a tick turning away. Level 3 is this, at a par of five.
• A memory wall blocks line of sight while it lives, so watching it also hides whatever stands behind it. It loses a memory point per unobserved tick, four by default and six in levels 6 and 10, and one glance refills it. Count your ticks looking away before you move.
• A stalker steps along the axis where the gap is larger and tries the other only when blocked. Walking into one does not kill you: you are blocked and lose the tick. Park them behind corners where their preferred axis meets a wall and they stall for free, no observation spent.
• You never observe the tile you occupy, so a drift platform under your feet always advances; to stop, step off. That blind spot also makes a mimic crate clone on the tick it leaves the cone, onto the free neighbour farthest from you. Level 7 needs exactly one duplication: two plates, one crate.

A little history

UNSEEN is an original puzzle written for this site, not a port of anything older. Its family is the turn-based grid puzzle, where the board is deterministic and the difficulty lives in the order of your moves; the crate pushing nods to Sokoban, published by Thinking Rabbit in 1982. What is new is that observation is the verb. Your gaze does not trigger traps, it pins the world in place, and every entity is a consequence of that one rule. Daily boards are built from the UTC date and then proved by a breadth-first search.

Frequently asked questions