A disc of mass, 27 cells across, grows into the gecko. Every cell runs the same trained rule: Fluoddity's Fourier brain reads the trail, the mass and six hidden numbers through two eyes, accelerates, and pushes its mass to where it lands. A small paint head carries the colour along. Nothing tells a cell where it is.
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The target, 128×128, one pixel per cell. T swaps the view to it. Wheel to zoom, drag to pan, double-click to recentre.