A small multiples chart displays winrates for a game, comparing opponents across a series of matches. Colored lines with smooth curves represent each opponent, and the legend maps colors to opponent names. The D3 code loads tab-separated data from a GitHub gist, uses `d3.line` with `curveBasis` for smoothing, and `d3.nest` to group by opponent. Axes are rendered with `d3.axisBottom` and `d3.axisLeft`, and a custom `colorLegend` function draws the color key.