Black technology. There are two rewards in the event chain of the mysterious fortress of the stars, one is black technology, and the other is that the whole galaxy becomes a wasteland planet. Although black technology is very powerful, it can blow up a bunch of planets with one explosion, and there are 30 squares of waste Saturn, which is very good. Mysterious fortress is a guardian space creature in the interstellar space, and it needs to install DLC Leviathan to appear in the game.