User blog:Sparkzzzz/Help with special dungeon

I just had a question about the special dungeon events where u can get ultra rare units. I don't know what I do wrong, but I can't enter any event. Do you need to clear a certain map or do you have to get at a very high level to enter these special events?

If I go to the Vortex I can only see the daily dungeon, the metal trade and Jewel trade....

Plz help