The final episode, 'Chapter Eight: The Rightside Up,' depicted Eleven seemingly sacrificing herself in the Upside Down after the defeat of Vecna.
Despite Mike's suggestion that Eleven faked her death and a glimpse of an older Eleven, the Duffer Brothers intentionally left her survival unclear, aiming for fans to interpret the outcome.
They explained that Eleven not ending up with the Hawkins group was a long-standing plan, symbolising the end of the characters' childhoods.
Matt Duffer clarified that the ambiguous sacrifice was intended to be courageous and heroic, preventing others from suffering, and its uncertainty reflects the characters' own lack of knowledge.