Gearing Up For Stranger Things Season 2? Don't Forget How Season 1 Ends

Nicknamed the "Demogorgon" by Will's friends, the monster (Mark Steger) is created during the experiments at Hawkins National Laboratory. Unbeknownst to Dr. Brenner at the time, he had accidentally created an alternate dimension aka the Upside-Down. The Demogorgon lives in the Upside-Down and feeds on people, taking the lives of lab technicians, local residents, and poor Barb, as well as kidnapping Will for a future meal. During the season finale, the creature has a showdown with Eleven at the local high school and is killed during their battle.