: Eleven defeats 001 by pushing him through a portal into the Upside Down , where the dimension’s environment transforms him into the monstrous Vecna . Why It Is Highly Rated
: Eleven's "mentor" in the lab is revealed to be 001 , the powerful first subject of Dr. Brenner's experiments. [S4E7] Plot Twist
This twist recontextualizes the entire series by connecting the current villain to the origins of Eleven's powers. : Eleven defeats 001 by pushing him through