The following post contains SPOILERS for Black Widow and specifically about the character of Taskmaster.
You might have been able to guess that fact from the headline that reads “‘Black Widow’ Writer Explains Origin of Film’s Taskmaster Twist,” but just in case there was any uncertainty, now there is not.
In the comics, Taskmaster has the ability to mimic the fighting moves of anyone he sees, making him a formidable opponent for any superhero.
It turns out that this Taskmaster is actually the grown daughter of General Dreykov, the leader of the Red Room that trained and brainwashed Black Widow in the first place.