Origin

Dark Beast an alternate universe version of the founding X-Men member and Avenger; Beast (Hank McCoy). Dark Beast's home universe was the Age of Apocalypse: a timeline skewed when Professor X died before ever forming the X-Men, and the Mutant tyrant Apocalypse conquered North America, threatening both humanity and much of mutant kind. Without the guidance of Charles Xavier, Hank McCoy's intelligence and pension for experimental science were allowed to flourish unhindered by the morals and compassion that are associated with his 616 counterpart. Acting as one of Apocalypse's chief scientists (and torturers), Beast's experimentation on humans and mutants alike were devious and highly unethical, earning him the name of "The Beast". He loved experimenting on anyone he could which included Scott and Jean of that reality.

After Age of Apocalypse

He was one of the four people from the age of Apocalypse to go Earth 616 (Nate Grey, Holocaust, and Sugar Man also ended up in Earth 616). Since Quicksilver messed with the trajectory, Dark Beast landed 30 years in the past on Earth 616. He met with a younger Emma Frost. She helped him regain his memories. He also created the Morlocks.

Pretending to be Beast

Dark Beast captured the real Beast and pretended to be the 616 Beast. He made sure nobody found out by killing childhood friends and teachers of 616 Beast. When Dark Beast tried to kill his parents, he could not. He continued to pretend to be Beast until Onslaught, where he joined Onslaught.

Gene Nation and Generation X

After a few run-ins with Gene Nation and Generation X, he became leader of the Gene Nation. He operated through a robot body named Wynter, in order to capture Generation X and experiment on them.

Finding a Cure

Dark beast has been searching for a way to reverse the effects of M-Day. Recently he confronted the Beast of Earth-616, who is working toward the same ends, and offered his help. The two have now formed a strained alliance in the pursuit of a way to avoid mutant extinction.

Powers

Dark beast shares many powers and abilities with the Beast of Earth 616. He possesses superhuman strength, agility, endurance, and speed. He has strong fingers and toes and can scale walls. Hank has great manual and pedial dexterity and can perform several tasks using both his hands and feet. He has enhance senses such as night-vision and a sense of smell that can track a human and also has a slight healing factor. He is highly intelligent and unlike his 616 counterpart, Dark Beast is unhindered by morals or compassion allowing him to think in ways that Beast would not and experiment in ways that Beast never would.

Due to his experimentation, Dark Beast is covered in dark blue fur, and has both claws and fangs. His hue is generally depicted as being darker than the Beast of Earth 616, and was often mistaken for the true Beast before the more feline appearance was created by his secondary mutation. Dark Beast never experienced such a secondary mutation, so his appearance is almost identical to how his 616 counterpart formerly looked.