Minecraft wiki entry for JSON_format, associated text: The game automatically arranges advancements, position them when it loads advancements from data packs, and sends the arrangement to the client. Each advancement has an arrow from its closest visible ancestor (i.e. if its parent does not have a display, it has a link from its grandparent, and so on). The root advancement appears on the leftmost column while each arrow points to an advancement in the next column. The arrangement of advancements within a column is based on file name.