Some content in this article is derived from information featured in The X-Adults: Endgame: The Latest Threat, and, as such, spoilers will be present.
Little is known about who is considered on this list. However, Mr. Demonic NoHead became the top of the list due to his revolution to overthrow Fobbles and the American government, which led to terrorist activities. Demonic, being a gifted and powerful dark mutant, gained much power and followers that made it very difficult to stop him. He managed to create the First NoHead Base to hold his prisoners and he caused much casualty, leaving him to be much feared, making his position as the #1 most dangerous dark mutant well deserved. His defeat at the hands of Saul Cameron resulted in Cameron becoming world renowned for his feat.
However, one generation later, after Mr. Demonic NoHead was defeated by Saul Cameron, the former Dark Lord's position as the top of the list was taken by Mr. Stupid NoHead, who were far more ruthless and cruel than Demonic, being more of a tyrant than a misguided revolutionary. Having engineered two wars to dominate the solar system, recreating and heavily expanding an army of followers and deadly creatures that caused more fear and causalities than the previous conflict, and actually temporarily succeeded in controlling the entire solar system. Many believe that Mr. Stupid NoHead was not human enough to die after his first downfall, furthering his superiority as a dangerous dark mutant, as he was unrepentant. Mr. Stupid NoHead's first and final downfall at the hands of Baby Intelligence made the latter a world famous hero.
- The X-Adults: Endgame: The Latest Threat (First mentioned)