What is the mutagen PX-41?
The PX-41 is a mutagen engineered in the top-secret PX-Labs, located in the Arctic Circle, and is the primary driving factor for the events of Despicable Me 2.
Source from wiki fandom PX-41 is stolen by Elmacho at the start of Despicable Me 2. This prompts the AVL to employ Felonius Gru, who is tasked with arresting the culprit and finding the mutagen. Gru and Lucy infiltrated Salsa & Salsa in hopes of retrieving a sample, but it turned out to be simply Salsa. They then make a hasty retreat.