Page tags is a useful feature, which really helps to navigate through a wiki. This wiki even has "Page Tags" link in the sidebar, as well as the "Page tags" section. But why don't we use them?
We can use general tags like "effect", "event", "area", "character", "menu". We can also use tags like, for example, "kaibutsu" - for all areas with Kaibutsu, and their own page, or "erosion" - for all things that affect the Erosion Counter, and the counter's page.