Beast (X-men: Evolution)

One of the first mutants that Xavier tried to reach, instead of confronting the beast he was turning into, Hank McCoy instead developed a serum that suppressed the rage inside of him.

Taking on the job as Science teacher at Bayville High, McCoy began having trouble controlling his rage again. Hoping to stop it before it hurt anyone, McCoy developed another serum, which dire consequences. Turning his skin into a blue fur, the mindless Beast was finally defeated by The X-Men, and Professor Xavier was able to return his mind to him.

With McCoy now a wanted fugitive, he realised he could no longer teach at Bayville, Xavier offered him a role as an instructor at his school, allowing him to teach young mutants how to control their powers and how to use them for the good of humans and mutants.

As well as teach the younger students; Beast was a pivotal player in the war against Apocalypse, where his knowledge of ancient Egyptian was used to learn the origins of Apocalypse, and his plans for the mutant race.

History
Hank McCoy attended high school in Bayville, and was even approached by Professor Xavier when he was a teenager. At the time though Hank turned down Xavier's offer of help and went on to become a chemistry and gym teacher. During the years Hank had managed to control his mutation through a serum he developed. The serum started to fail however and he eventually lost control and mutated into the "Beast". As the Beast he caused massive destruction and is now a wanted fugitive. After his first transformation he was able to regain control, but he has now become permanently trapped in the physical form of the "Beast". Unable to return to his life as Hank McCoy he has chosen to join Xavier's school and now helps to teach the New Mutants.

Power and Abilities
Genetic Atavism: It is possible that Beast's mutation is a result of genetic atavism (or genetic traits that resurface in a species after many years of dormancy). He also possesses neotenous (or traits in a descendant that resemble those of an ancestor organism) characteristics, which would explain why he has a big modern brain with an ape-like physique.

Due to secondary mutation Beast transformed from his original ape-like physique to a more cat-like physique. A next mutation affected him, and he required the help of his past-himself, who was able to stabilize him in an appearance who bears very little resemblance to one of his counterparts: The Brute.
 * Superhuman Strength: The Beast has always possessed some degree of superhuman strength, the limits of which have varied at times due to subsequent mutation. During his teens, he was able to lift approximately 1 ton. After mutating into his simian form, and after this mutation eventually stabilized, his strength was increased to the point where he could lift about 10 tons, which was sufficient to smash through a brick wall with a single punch and to tie an iron barbell into a knot.
 * Superhuman Speed: The Beast can run and move at speeds that are slightly beyond the natural physical limits of the finest human athlete. He can run at speeds up to 40 miles an hour over short distances, particularly if he runs on all fours.
 * Superhuman Stamina: The Beast's highly advanced musculature produces less fatigue toxins during physical activity than that of an ordinary human. He can exert himself at peak capacity for several hours before the build up of fatigue toxins in his blood begins to impair him.
 * Superhuman Durability: The Beast's bodily tissues are harder and more resistant to certain types of injuries than the bodies of normal humans. His physiology can withstand great impact forces, though he can be injured by many types of conventional weapons such as standard firearms and bladed weapons. However, he can withstand physical impacts, such as falling from several stories or being physically struck by many super-humanly strong beings that would either severely injure or kill a normal human with little to no discomfort.
 * Superhuman Agility: The Beast's agility, balance, and bodily coordination are enhanced to levels that are beyond the natural physical limits of the finest human athlete. Like some of his other powers, his agility has varied at times due to ongoing and subsequent mutations. While in his simian form, he had the agility of a great ape combined with the acrobatic prowess of an Olympic level gymnast. He could walk a tightrope or a slack rope as easily as most people can walk on a sidewalk. He could also walk on his hands for many hours, or perform a complicated sequence of gymnastic stunts such as flips, rolls, and springs. He could easily match or top any Olympic record in gymnastics..
 * Superhuman Dexterity: He can perform many tasks with his feet as easily as a human could do with his hands. His manual and pedal dexterity are so great that he can write using both hands at once or tie knots in rope with his toes.
 * Regenerative Healing Factor: The Beast's metabolism enables him to repair mild to moderate injuries much faster than a normal human. For instance, he can recover from minor ailments, such as a severe cold or fever, within a few hours. More severe injuries, like broken bones, can heal within a few days, whereas normal humans might take many weeks or even months.
 * Super-humanly Acute Senses: Hank possesses enhanced, acute senses that are comparable to those of certain animals, enabling him to see and hear distant objects more clearly than a normal human, and identify and track someone purely by scent. He also possesses cat-like night-vision.
 * Pheromones: Beast has the ability to secrete pheromones to attract members of both sexes.
 * Claws and Fangs: The Beast sports retractable, razor sharp claws at the tip of each finger and toe. Their natural edge, coupled with his strength, are sufficient to rend most conventional materials including flesh, wood, stone, and even some types of metals. He also possesses elongated canines that he can use, if he chooses to do so, as effective weapons in close quarter combat situations.