HELIOS — The Longest Day: A light-routing logic puzzle game submission for the June Solstice Game Jam

HELIOS — The Longest Day is a real-time light-routing logic puzzle.

On the longest day of the year, sunlight is your only tool: you bend the sun's beam with mirrors, divide it with splitters, and channel it through optical logic gates to wake dormant crystals before the sun sets.

The goal was to fuse the two themes into a single mechanic instead of bolting them together

So it's not light-as-decoration. Light is the gameplay, and logic gates are the core mechanic.