If you’ve been interacting with ChatGPT recently and observed it making peculiar mentions of goblins, gremlins, ogres, or trolls, you aren’t imagining it. OpenAI has clarified the reasons behind this unusual ChatGPT behavior and the steps being taken to resolve it.
How a ‘nerdy’ quirk became everyone’s problem
OpenAIThe issue quietly began with GPT-5.1, released in November. Following that update, the frequency of the word “goblin” in ChatGPT outputs surged by 175%, while “gremlin” usage climbed by 52%. The root cause was traced to one of ChatGPT’s optional personality settings labeled “Nerdy,” which was intended to give the AI a more playful and intellectually inquisitive tone.
OpenAIDuring the training phase, OpenAI inadvertently assigned unusually high rewards to responses containing creature-based metaphors, causing the habit to develop rapidly.
How did a single personality setting cause so much goblin talk?
OpenAIHere’s where it gets interesting. Even users who never switched on the Nerdy personality started seeing goblin references pop up in their chats. That’s because AI training isn’t contained to one setting. Once the ChatGPT model was rewarded for that style, the behavior bled into general responses across the board.
OpenAIOpenAI says the Nerdy personality made up just 2.5% of all ChatGPT responses, yet accounted for 66.7% of all goblin mentions.
So how is OpenAI actually fixing this?
OpenAIOpenAI retired the Nerdy personality in March with ChatGPT-5.4, which caused goblin references to drop sharply. The company also stripped out the reward signal driving the behavior and filtered training data to reduce references to other magical creatures.
OpenAIIts coding tool, Codex, however, needed a separate override instruction since it had already begun training before the root cause was identified. Fantasy fans can still unlock goblin mode in Codex manually, if that’s your thing.
OpenAI is also dealing with other personality-related decisions, including putting its previously teased adult mode for verified users on hold indefinitely.