Created by Ra’s al Ghul and brought to Gotham City by his servants, Whisper A’Daire and Kyle Abbott, the Elixir was intended to be sold as an expensive longevity drug, keeping those who took it young and healthy for as long as they did. It was also a potent mutagen, causing each user to develop the traits of a different animal. It was intended to sow chaos and disorder throughout Gotham, and might well have done so if no one intervened.
The Batman is, of course, all about these kinds of interventions. He identified the source of the drug, its alchemical origins, and its effects, and managed to bring A’Daire and Abbott’s plans to a stop while destroying all supplies of the Elixir before it hit the streets. And a good thing too.