The Jagerdraught (or, if you like, Jagermeister) definately exists -- it's now canon (as per the recent strip) but it was specfied by Kaja, like, ages ago -- that the Jagers were created by "here, drink this" rather than by any other mechanism.

(Surprised the GGgame team didn't know this, actually, but then, not everyone follows the yahoo group and Kaja's blog).