You never cast a spell. You cast a rainbow.

One shaft of dawn strikes your horn and leaves it as seven bands of light. Each band is a different verb. They fire together, always, in a rigid fan — so every shot is seven decisions at once, and you aim the whole spectrum or none of it.

Plays in your browser. Free. The entire game is 13,312 bytes.

The seven verbs

  • UNMAKE — dissolves the made
  • FORGE — hardens into matter
  • WAKE — animates the dormant
  • GROW — accelerates living things
  • CHILL — slows and stills
  • SCRY — reveals what is hidden
  • MEND — restores what it touches

The trap is in that list, not in the difficulty. GROW is your entire economy — it ripens the blooms that pay you in Light. It is also the fastest way to breed a monster, because the blight standing beside that bloom is a living thing too, and GROW does not know the difference. MEND heals your cairns and it heals whatever is eating them. FORGE hardens your ground and it armours the thing standing on it.

You cannot fire one band. That is the game.

What you actually control

Two keys. Q narrows the fan to a lance — everything on one target. E opens it into a curtain that touches the whole hillside thinly. The order of the bands is spectral and never changes, so unsealing a new one alters geometry you have already learned rather than adding a number to a list. SPACE flares: the bands reach further and hit harder, paid for out of your vigour.

Falling is not losing

Run out of vigour and the light goes out — and you keep every upgrade, every band, and every mote of Light you were carrying. You walk back into the same valley from the Prism. There is no run to lose and nothing to grind back. It saves automatically.

13,312 bytes

Built for js13kGames 2026 — theme “Unicorns and Rainbows” — where the whole game, zipped, must fit in 13KB. There are no image files and no audio files in this game at all. Every flower, every band, the unicorn herself and the whole moor are drawn by the code as it runs; every sound is synthesised from oscillators in the same file. That constraint is not a limitation here, it is the craft.

Full source is published unmangled and MIT licensed, as the jam requires.

More free browser games and developer tools from Core Systems Asset Factory: csaf.itch.io

More free browser games from CSAF

Every one of these plays in one click. No install, no account, and they all save as you go.

  • HALFLIGHT — Everything in the vault is decaying. That is what pays you.
  • OTTERBOUND — Six otters, one raft, and a river that never ends the same way twice.
  • CHARGE BARGE — Drive a storm-powered ironclad up an insane hostile coastline.
  • RUSTBLOOM — You never find the key. You forge it.
  • THE LAST FLOCK — Your army is a crowd you shape with movement alone — and it dies.
  • BANNERET: SUCCESSION — You never move a knight. You plant a banner.
  • STARCHART — Every voyage you fly is inscribed forever. The route you took IS the constellation.

We also make the parts

Core Systems Asset Factory builds pixel-art packs and engine tooling for developers. If you build games as well as play them, these are ours:

Plus plugins and editor tools for RPG Maker MZ, GameMaker, Unity and Unreal — the full catalogue is here.

More information

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