Task Master 
The Task Master is a formidable foe to many Marvel heroes. possesses the ability to absorb knowledge and instantly replicate combat skills of anyone he observes. He has used these skills as a teacher to many super villains, henchmen, and even some heroes. One of the more fascinating things about the Task Master he has what he calls “photographic reflexes”. After seeing someone perform an action once, he can perfectly copy the action. The people he has copied styles/skills from include: Beast, Black Knight, Black Widow, Bullseye, Captain America, Cat, Daredevil, Deadpool, Elektra, Hawkeye, Hulk, Iron Fist, Mister X, Ms. Marvel, Porcupine, Photon (Genis-Vell), Puma, Punisher, Quicksilver, Razorfist, Scarlet Witch, Shang Chi, Silver Samurai, Spider-Man and many, many more. (In crossovers he has learned the skills of Batman and Huntress. Which makes him quite a foe to be reckoned with.
