Parallax Prism: Rules in Motion

About Parallax Prism: Rules in Motion

Parallax Prism: Rules in Motion is a physics puzzle set in a gravity research station, where a glowing probe is released from an emitter and falls whichever way the station pulls. Somewhere on the dark test plate waits a catch cup, and between the two lie empty hexagonal sockets and a few blueprint stamps to fill them.

There are three stamps. A rising ramp (/) and a falling ramp (\) turn the probe like a mirror turns a ray of light; a bumper sends it straight back the way it came. A probe carried sideways that meets a wall falls back into gravity's direction, and one that meets a wall in gravity's own direction comes to rest, so the cup has to be reached on the way. Black drains swallow the probe, and a probe that circles for ever is a loop.

Then the rules move. Every experiment has two tests. Pass the first and one rule of the station changes before the second: gravity turns to another side, the ramps' lenses invert so that / acts as \, or the catch cup is moved to a new place. Lift, add and swap stamps until the second test passes too, and the stars count the stamps on the plate against the fewest the game's own solver found. Twelve hand-ordered experiments bring in one change at a time, then spare experiments from the station archive without end and a daily experiment that is the same for everyone. Nothing is timed. Your progress stays in this browser.

How to play

Guide the probe from the emitter into the catch cup.
Pick a stamp in the tray, then tap an empty socket to press it; tap a stamp again to lift it.
Ramps turn the probe like mirrors; a bumper sends it back. Drains swallow it.
Press Drop. When the first test passes, a rule changes: adapt the device and test again.
Fewer stamps on the plate earn more stars. There is no clock.

Controls

Tap or click a tray stamp, then a socket — press it; tap a stamp again to lift it
1, 2, 3 — pick a stamp; arrow keys, WASD or D-pad — walk the cursor over the sockets; Enter — press; X — lift
Space, RT or Drop — run the test; H — a hint
Backspace, Z or Undo — undo; R or Reset — clear the plate
P, Escape or Start — pause

Frequently asked questions

How does the probe move?

It is released from the emitter and falls the way gravity pulls. A ramp turns it like a mirror: a rising ramp (/) sends a falling probe left and a probe moving right upward, a falling ramp (\) the opposite. A bumper sends it back. A probe moving sideways that meets a wall drops back into gravity's direction; one already moving that way stops on the wall.

Why did the probe not reach the cup?

It came to rest short of the cup, was swallowed by a drain, or circled in a loop. The cup catches the probe the moment it enters, so the path has to pass through it; read the test result under the plate to see where the probe ended.

What changes after the first test?

One of three things, shown on the change card before you start: gravity turns to another side, the ramps' lenses invert (a rising ramp acts as a falling one and back), or the catch cup is moved. Your stamps stay on the plate, so you only adapt them.

How are stars counted?

By the stamps on the plate when the second test passes, against the fewest the solver found. A hint limits that experiment to two stars. Tests, undo and clearing the plate are free.

Can I play without telling the colours apart?

Yes. The two ramps are drawn as slanted bars leaning differently, the bumper as a spring, and every stamp has a name in the tray. Every test is also described in words for screen readers.

Does the game save?

Yes, in this browser: solved experiments, stars, and the plate you were working on, including which test you are on. Nothing is uploaded.