Hercules
Hercules engaged in battle with the Hydra at the Lernaean Swamp.
Hercules killed the Hydra in Greek mythology by cutting off its heads, and then cauterizing the neck stumps to prevent them from growing back.
Hercules killed it so I assume him.
The second labour of Hercules was to defeat Hydra
Hercules defeated the Hydra by cutting off its heads, and with the help of his nephew Iolaus, he cauterized the neck stumps to prevent them from growing back.
They didnt invent it, it was there when it got defeated by Hercules.
Hercules
When Hercules was fighting Hydra, the nine headed serpant monster, a crab scurried up and pinched Hercules' toe. This crab was a distraction in the battle, and Hercules killed it. The greek goddes Hera was impressed with the crab, and showed it's picture up in the sky.
He did many tasks for his master such as killing the Hydra and a great lion
it was trapped in a cave until Hercules accidentally unleashed it (but it was shortly killed)
in the Hercules film, he stops and sears at the hydra after he cuts off some heads and i saw the hydra had 27 heads and also had 29 heads when Hercules is falling into the hydra
The Hydra but it is interesting to note that it was the Hydra that did Hercules in at the end.