Goal: power every reactor with the right beam color.
Play: click mirrors, splitters, or prisms to rotate them.
Lab parts: filters recolor beams, portals teleport, splitters branch beams.
V3: vector prisms have four directions. Color gates only open for matching beams.
Overdrive: switches unlock gates, diodes are one-way, and numbered reactors must fire in order.
Apex: hard packs hide live beams. Scan reveals the route briefly and costs one move.
Keys: R resets. N moves to the next solved level.