Mar Novu

"You failed." "Why are you doing this?" "You did this to yourself. And now, all of you will perish."

- The unnamed individual and an unidentified speedster

An unnamed individual is presumably the cause of the destruction of Earth Ninety.

History
The individual presumably murdered many superheros on Earth Ninety. At one point, a speedster was crawling on the ground, trying to get a book that was on the ground. However, the individual grabbed the book first. As the Flash asked him about his actions, the individual explained that he did it to himself. He then opened the book, while the Flash ran away from the scene.