PRISM

PRISM — a light puzzle for the Commodore 64.

Somewhere in the dark a lamp shines white. Around it wait the targets: rings that glow only when the light reaching them is exactly their colour. Red wants red. Cyan wants cyan. White wants everything at once.

Turn mirrors, slide prisms, aim lenses and drop filters into the beam. Split white light into red, green and blue, take a colour away, mix two back together, and bring every target its own colour at the same time. Then the border breaks into a rainbow and the next room opens.

• 64 levels, each checked by a solver: one idea at a time first, then light split, filtered, mixed and folded back on itself
• Six pieces: lamps, mirrors, filters, prisms, lenses and targets
• Light that travels: beams shimmer, new light races out from the lamps, targets ring like bells
• Par for every level and up to three stars (you may beat the solver)
• Eight dark synthwave songs for the SID chip
• Every level open from the start

Play the demo in your browser (the first 12 levels), or download the full game: Windows and macOS downloads include the VICE emulator and start with a double-click. prism.d64 runs on any C64 emulator or a real PAL C64. The manual explains every piece and the colour rules, and ends with how the game works inside.

Keys: arrows move · space turns · space + arrows drags · R restart · Esc menu · M / N music

macOS: the download is not from the App Store, so the first time macOS may refuse to open it: right-click PRISM, choose Open, then Open again (or System Settings › Privacy & Security › Open Anyway).

Made in 6502 assembly. Runs in VICE 3.10 (GPL); the web demo uses EmulatorJS (GPL). © 2026 kpatronas.