With the release of Stranger Things Season 2 we have also the release of Beyond Stranger Things, the deep dive aftershow, where the actors, showrunners, and directors talk about their process in creating the characters and the monsters of Hawkins. Early on in their discussions we learn that despite the fact that this season's "Big Bad" is called "The Shadow Monster" by all an sundry, it has another name: "The Mind Flayer." What is a Mind Flayer on Stranger Things Season 2? And how does it tie back to Dungeons and Dragons? Please be advised: This post contains spoilers for Stranger Things Season 2.
First, we should note, going into this season most fans assumed that the big bad would be based on a Dungeons and Dragons character called "the Thesselhydra." That was the monster we saw the boys defeat in the epilogue round of the game.
But this season didn't conform to expectations. D&D was no longer the game everyone played on screen, leaving it behind for the arcade. (Though their D&D roles are still how the boys define their friend group, aka "The Party.") And when the Duffer brothers sat down to make this season's monster, they decided they needed some a little less "mindless" than a Demogorgon, which they compare to the shark in Jaws. Sure the Demogorgon was deadly, but not exactly intelligent, as much as it was killer instinct.
What they came up with instead was the creature that was referred to mainly as "The Shadow Monster" who the Duffers even say was more like "a Voldemort type character," a malevolent evil, but intelligent. And for a goodly amount of the production of Season 2, that's what everyone called it. There wasn't a good tie back to D&D for it.
That is, until one of the Duffers (Matt) apparently was thumbing through a Dungeons and Dragons monster manual and happened upon the creature known as "The Mind Flayer."
Mind Flayers, which are also known in the game as "Illithids" are a sentient creature called "the scourge of sentient creatures across countless worlds." To wit:
In eons past, illithids controlled empires that spanned the planes. They subjugated and consequently warped whole races of humanoid slaves, including the githyanki and githzerai, the grimlocks, and the kuo-toa. Conjoined by a collective consciousness, the illithids hatch plots as far-reaching and evil as their fathomless minds can conceive.
Since the fall of their empires, illithid collectives on the Material Plane have resided in deep in the Underdark.
The Upside Down could definitely be considered "the Underdark." And the enslaving of minds and warping of humanoid type races certainly fits what happens to Will when he stops running and the Shadow Monster reaches forth those tendrils and enters his head.
The Shadow Monster doesn't resemble the drawings of Mind Flayers*, but then again the Demogorgons (and now demodogs) don't look like anything from Dungeons and Dragons either. It's more about taking the metaphorical concept of the creature that a literal interpretation.
(*The illustrations from D&D make Mindflayers look more like angry Oods, which would probably upset Whovians highly.)
Speaking of which, having a monster who is not sentient also ups the stakes for Season 3. As we saw at the very end of Season 2, the Mind Flayer/Shadow Monster is poised over the Upside Down's version of Hawkins Middle School Gym, where, at that very moment, Eleven, who defeated him, and Will, the boy he was once connected to, are dancing the night away to classic '80s tracks.
That the Mind Flayer can track where they are in their world, while still being in his own is a very worrisome development. Yes, Eleven closed the gate. But what no one seemed to ask themselves is if there was a way for it to be opened again. Especially by those in the Upside Down (or as we learned in the after show "the Nether") who want to come through and conquer.