This example overlays Pokémon sighting locations onto a Leaflet map of Taiwan using colored, diamond-shaped markers that encode each creature’s primary type. It loads a CSV of Pokédex entries via `d3.csv`, filters for a target species, and maps coordinates through Leaflet’s `L.marker` and `L.divIcon`. An OpenStreetMap tile layer and an image overlay provide geographic context, while a color dictionary maps type names to hex values for the custom HTML marker styles.