I am hoping this gets added as a catagory.

Leave it completely blank as far as tracking goes, but use it for achievments such as each of the invasions.
Or the heralds.
Or the new purple gate quests and so on.


Things that people need to figure out and find on their own, but are not shown in updates and are secrets within the game themselves or are limited time events.


Basicaly, a way for them to show up when you earn them, but if you havent they wont show up at all in your UI acievement section, because after all once gone, they are unobtainable.