Read the chamber before moving an instrument
Start with the lamp and the gate lenses. Each Prism Riddle chamber has its own source position and direction: light may arrive from a side wall, rise from below, or descend from an upper alcove. Follow the initial beam until it meets a barrier. Then look for the opening that would take it into the next part of the chamber. This gives you a route to investigate before you start adjusting every instrument.
The gate panel tells you the required light color, minimum energy and, where relevant, color purity. A crossed lens has the opposite job: it must remain dark. The small progress indicators show what your current arrangement actually delivers. Reaching one gate does not complete a chamber that has several gates.
A five-step solving loop
- Trace the first collision.Follow the lamp until stone or glass stops its current path.
- Choose the next opening.Work one passage ahead instead of aiming directly at a distant gate.
- Place before rotating.Put an instrument fully inside the beam, then adjust its angle in small steps.
- Read the gate panel.Separate direction problems from width, energy and color-purity problems.
- Protect a useful section.Once part of the route works, change only the next instrument and use undo when an experiment fails.
Build the route with mirrors
A mirror changes the direction of light, but its useful surface has a finite length. If only the edge of a wide beam hits it, only that part follows the reflected route. Move the mirror into the beam and turn it gradually. In a corridor puzzle, align the next opening first and then work on the next turn. Rotating one mirror changes the direction of every part of the path after it.
Drag the instrument itself to move it. Drag the round handle to rotate it. You can also select an instrument from the numbered list and use the angle slider or the position fields. On a keyboard, the arrow keys move a selected instrument and Q or E rotates it; hold Shift for smaller adjustments.
Use lenses when direction alone is not enough
A wide beam can reach the correct place and still lose most of its energy at a narrow opening. A convex lens can gather it toward a focus. The important question is where that focus lies along the full light path, including reflections. A concave lens spreads parallel light, and it can also change an already converging beam. Some chambers need two lenses to produce a narrow beam that stays useful farther along the route.
Check color and energy after each branch
A beam splitter divides the incoming energy between reflection and transmission. It does not give both branches a full-strength copy. A color filter then removes unwanted wavelengths, reducing the energy again. If a gate receives the correct color but still lacks energy, look for clipped beams, extra splitting or unnecessary filtering along its route.
Every supplied instrument must participate in the formal puzzle. You can explore different valid arrangements; the game checks the resulting light instead of comparing your positions to one fixed diagram.
Diagnose the most common failed routes
| What you see | Likely cause | What to try |
|---|---|---|
| The beam touches a gate but it stays closed | Too little matching energy reaches the lens | Center the beam on each instrument and remove clipping at narrow passages |
| The correct color arrives weakly | A splitter or filter removed energy earlier | Collect more of the incoming beam before filtering |
| A route works until one mirror is turned | Every later angle depends on that reflection | Realign the route from the changed mirror forward |
| All lit gates look correct but the level does not finish | A crossed target receives stray light, or a tool is unused | Inspect dark targets and the participation count |
Keep a useful experiment, undo the rest
Undo and redo let you compare changes without losing a promising layout. Hints reveal a route idea first, then more specific guidance. The timer starts with your first instrument operation and pauses when the tab is hidden. Completion records and personal best times stay in your browser. A challenge link opens the same chamber for a friend, while your own solution and purchase access stay private.
The first three chambers are free, including a prism-dispersion puzzle. The free workshop gives you room to try the tools without a gate to satisfy.
New instruments in the expanded observatory
A dichroic mirror passes its marked color and reflects the other bands into another route. A neutral density filter reduces all wavelengths by the same transmission factor. Some splitters use 30/70, 40/60 or 60/40 energy ratios, so each branch needs its own budget.
Sensitive gates show an upper total-energy limit as well as the usual minimum matching-energy requirement. A bright beam can overload them. Use the neutral density filter to bring that branch into range while keeping the other gates illuminated.
What changes after the three free chambers
The free sequence teaches a multi-mirror route, a two-lens relay and a complete prism-and-filter path. The full collection keeps those ideas in play while adding two lamps, divided energy, several colored gates, protected dark regions and larger chambers with up to 22 instruments. A full-game purchase unlocks the advanced chambers as a single purchase rather than a subscription.
If you want to practise one device in isolation, switch to the free lab. Formal levels require every supplied instrument to carry light, while the lab lets you add, remove and rearrange tools without campaign scoring. You can move up to four lamps, add receivers, adjust beam and filter settings, and save or share your experiment.