With every new possessed body, it grew larger and larger until it was destroying buildings in its efforts to kill Eleven, and it was personified by none other than Billy (Dacre Montgomery) and newcomer Heather (Francesca Reale).
The long-awaited third season of Stranger Things has finally arrived and, as promised by the teases in the trailers, it delivered a monster that was terrifying to behold.
While it was the manifestation of the Mind Flayer again, Stranger Things did something brand new by introducing it as a creature literally made of its victims.