Mind Flayer's first appearance.
Mind Flayer being seen by Will Byers during his episode.
On Halloween night, Mind Flayer begins to emerge into the sky in the Upside Down when Will has another episode.
Mind Flayer still emerging as the Mind Flayer.
Mind Flayer appearing to Will.
Mind Flayer fully emerged as he spots Will.
Mind Flayer chasing Will before Mike Wheeler snaps him out of his episode.
Mind Flayer's mist appearing in Hawkins Middle School.
Mind Flayer chasing Will through the hallways of the school.
Will standing his ground against Mind Flayer.
Mind Flayer approaching Will.
Mind Flayer ignoring Will's demands to leave him alone as he reaches towards the boy.
Mind Flayer bending one of his mist pockets.
Mind Flayer trapping Will in his pocket where he begins to possess him.
Mind Flayer begins possessing Will.
Mind Flayer possessing Will.
Mind Flayer finishing his possession of Will before transporting the boy back to the real world.
The Mind Flayer's fragment leaving Will's body.
The Mind Flayer leaving Will's body after Nancy Wheeler, Jonathan and Joyce Byers expose Will to heat.
The Mind Flayer coming out of Will's body as Jonathan watches in horror.
The fragment of the Mind Flayer having left Will's body.
The Mind Flayer's fragment flying out of Jim Hopper's cabin.
The Mind Flayer's fragment disappearing into the night sky.
Eleven repelling Mind Flayer's last effort to breach through.
Eleven sealing Mind Flayer.
Mind Flayer back in the Upside Down.
Mind Flayer's fragment reawakening due to the Gate being reopened.
Mind Flayer's fragment regaining shape.
The fragment of Mind Flayer now fully awake.
Mind Flayer appearing before Billy as silhouettes in the Upside Down.
Mind Flayer approaching Billy.
Mind Flayer appearing as Billy, much to the real Billy's shock and horror.
"To build. I want you to build."
(Billy: "To build what?") "What you see."
Mind Flayer about to vanish before Billy is transported back to the real world.
The Mind Flayer emerging out of the shadows to possess Heather Holloway after Billy kidnaps her.
Mind Flayer having melted Tom Holloway's corpse after he is killed by Jonathan.
Mind Flayer having melted Bruce Lowe's corpse after he is killed by Nancy.
Mind Flayer taking control of Tom's melted flesh.
Mind Flayer taking control of Bruce's melted flesh.
Mind Flayer making Tom's flayed flesh crawl towards Bruce's flesh.
Mind Flayer making Bruce's flayed flesh crawl towards Tom's flesh.
Mind Flayer controlling the flesh thralls.
Mind Flayer merging the flesh of Tom and Bruce together.
Mind Flayer as an asymmetrical monster created from the flesh of Tom and Bruce.
Mind Flayer charging at Nancy.
Mind Flayer chasing Nancy through the hospital.
Mind Flayer trying to get into a room Nancy entered, only for the girl to have locked the door.
Mind Flayer going to ooze underneath the door.
Mind Flayer's proxy oozing through the door.
Mind Flayer having entered the room Nancy's in.
Mind Flayer's proxy rebuilding its body.
Mind Flayer's proxy pinning Nancy down.
Mind Flayer's proxy roaring in Nancy's face just as it is about to kill her.
Mind Flayer's proxy seeing the Party has come to Nancy's rescue.
Mind Flayer's proxy charging towards the Party.
Mind Flayer's proxy being thrown against a wall by El.
Mind Flayer's proxy being thrown into the ceiling by El.
Mind Flayer's proxy on the ground.
Mind Flayer's proxy having recovered just as it goes to attempt to attack the Party again.
Mind Flayer's proxy having splatted on the ground after being pushed out a window by El.
Rather than rebuild a body, the Mind Flayer's proxy crawls away as the Party watches it escape.
Mind Flayer's proxy escaping into a sewer.
The Mind Flayer's avatar walking through the forest.
The Mind Flayer's tentacle having burst into the Hopper cabin to attack the Party.
The tentacle being shot at by Nancy.
The Mind Flayer's tentacle being immune to Nancy's bullets.
The tentacle charging at Nancy when she runs out of bullets.
The Mind Flayer's tentacle coming close to killing Nancy.
The tentacle being telekinetically restrained by El before she snaps it in half.
After El snaps two more of its tentacles, the Mind Flayer ambushes her, using a tentacle from his mouth to grab her by the leg.
The Mind Flayer seeing Max Mayfield, Mike Wheeler, & Will trying to save El as they grab onto her.
The Mind Flayer getting close to eating El.
The Mind Flayer getting shot by Nancy, causing him a little bit of pain.
The Mind Flayer seeing Lucas Sinclair chopping his tentacle with an axe.
The Mind Flayer being distracted as Nancy keeps firing her gun at him.
The Mind Flayer losing his grip on El after Lucas manages to severe his tentacle.
A piece of the Mind Flayer's tentacle still clinging onto El's leg.
The piece of the tentacle biting El before Mike rips it off her leg.
The piece of the tentacle crawling away.
The Mind Flayer looming down over the kids as they recover.
The Mind Flayer's avatar roaring at the Party.
The Mind Flayer's avatar roaring angrily as it proceeds to attack the Party again.
The Mind Flayer's avatar being telekinetically restrained by El.
The Mind Flayer's head getting telekinetically ripped in half by El.
The Mind Flayer's avatar's head ripped in half.
The Mind Flayer recovering and regenerating his avatar body as the Party escapes.
Mind Flayer searching for the kids at Starcourt Mall.
Mind Flayer's avatar on the roof of Starcourt, seeing the Party escaping.
Mind Flayer chasing the Party.
Mind Flayer pursuing the Party throughout Hawkins.
Mind Flayer stops pursuing the Party when the Flayed Billy spots Mike, El, and Max back at the mall.
Mind Flayer's avatar about to kill El.
Mind Flayer getting hit with fireworks.
Mind Flayer attacked by Lucas, Will, Nancy, Jonathan, Steve, and Robin who throw fireworks at him.
Mind Flayer pelted with fireworks.
The Mind Flayer hit by a green firework.
The Mind Flayer being pelted by fireworks that the kids throw at it.
The Mind Flayer being pelted with so many fireworks.
The Mind Flayer hit with a red and pink firework.
The Mind Flayer pelted by fireworks as the possessed Billy stops El from escaping.
The Mind Flayer pelted with fireworks as the Party fights it.
Mind Flayer enraged at Billy for resisting his mind control.
Mind Flayer killing Billy.