When the Grand High Witch created Formula 86, it was a massive technical success. Compressing an entire human into an average mouse? The other witches were amazed the world over. It was absolutely genius!
But, surprisingly, the witches operate more scientifically than one would expect- with each additional success in their field, more questions popped up that must be answered. For instance- Each subject that ingested Formula 86 expelled a massive amount of green gas during the conversion process. "So", the witches thought, "what if we force the gas back into one of those disgusting humans?"
The answer was formula 87. All the mass that a human lost when turning into a mouse had to go somewhere, and it turns out that somewhere was the green gas. So, when you stuffed it back into someone, it turned that human into a porker. (Quite literally, it would appear.) And with the coming holiday, they had the ability to distribute the formula en masse...

Done by  KitsuneKit