Thanks you, but that article has too many details. I would like a brief summary.

1. Admins and users given the "map-tester" group by an admin (of the wiki)

2. There is no limit on the number of people editing a map (though there might be issues when two people edit it at the same time) or the number of maps on a wiki

3. Displaying maps, also useful for people to explore

Thanks you old buddy!

{
  "origin": "bottom-left",
  "coordinateOrder": "xy",
  "mapImage": "File:MapBackground.jpg",
  "mapBounds": [[0, 0], [1000, 1000]],
  "categories": [
    { "id": "1", "name": "Artifacts", "color": "#ff00ff" },
    { "id": "2", "name": "Dungeons", "color": "#00ff00" }
  ],
  "markers": [
    {
      "categoryId": "1",
      "position": [500, 300],
      "popup": {
        "title": "A Sword",
        "description": "Very important artifact",
        "link": {
          "url": "Article about a sword",
          "label": "See more"
        }
      } 
    },
    {
      "categoryId": "2",
      "position": [300, 500],
      "popup": {
        "title": "A Cave",
        "description": "Very scary dungeon",
        "link": {
          "url": "Article about a cave",
          "label": "See more"
        }
      } 
    }
  ] 
}

There's the code.

FYI, this is a new feature which came out less than a week ago. So, unless someone has been obsessed with learning it these past few days, it is unlikely you will find any user who knows the ins and outs of the feature even if they have been on Fandom for years. There is a small handful of users who had access to early testing but I am not aware of any who also frequently contribute to Discussions on Community Central. So, essentially, we are all learning about this feature together.

Maps aren't that complicated technically, and the visual editor for them works very well. 99% of what anyone would have to do for a map is point at where they want a marker to be and then fill in the form. Special:AllMaps will have a form you can use to get taken to the map editor (or just go to Map:Whatever) and then just upload an image, create some categories, and add markers.