Past research - Hydra - Powder of Lerna - Commission

Lerna's powder comes from an alkaline, chalky rock found mainly in the Lerna region of Greece. Once ground to a powder and mixed with a binder, often egg white or fish glue at the time, this powder gave a golden glaze that was highly prized on pottery.

But that's not its only interest. It is also known to be the origin of one of the most famous mythological creatures : the hydra. Originally a serpent with several heads, one of which was immortal, it was often made of gold.
Surprising as it may seem, this effect is not triggered by inhaling the raw powder, but after an exposure to high heat. It is perfectly possible to handle freshly extracted Lerne rock and breathe in the dust without the slightest problem (except for mortals lungs). The transformation effect is only possible after firing, for example as a glaze on a vase. Once inhaled or ingested, the powder transforms an organism into a hydra.

This charming young kitsune, procene , wanted to borrow my Lernaean vase for some in-depth studies.
I no longer have a vase, but I do have a living hydra in my library now.