A hydra or hydrae are - mythically and in RPG terms at least - reptilian carnivores with a number of serpentine heads growing from a single body. The shape of the body is up for grabs - some sources show a quadruped one, others snake like whilst some compromise with a wyvern-like snake with two extra legs.
The prototype of this creature was the Lernaean Hydra from Greek mythology - the offspring of Echidna and Typhon (both fairly monstrous in their own right) - which had the added amusing features of regenerating two heads for every one that was severed and having highly toxic breath and blood1. In the end, the beast was defeated by Heracles with this assistance of his nephew Iolaus who cauterised the stump of each neck as the heads were cut off, preventing regeneration. The one immortal head was severed and buried under a large rock, from where it was said to continue to polllute at least one local river. Why Heracles - whose signature weapon was a club felt the need to cut the heads off in the first place is not entirely clear.
Subsequent fictional - and more often RPG - hydras usually maintain the multiple headed aspect and in many cases the multi headed regeneration and breath weapons as well. Often there is a sliding scale of hydras based on number of heads and optional features installed.
In real life the hydra is a deeply unimpressive looking microscopic animal similar to a jellyfish found in fresh water all over the planet and named for the multiple 'arms' that it grows from a single trunk. Ironically, it turns out that real life hydras have a poison sting, seem to be very good at regenerating and may or may not be immortal (or at least unaging). Nominative Determinism is a wonderful thing.
Game and Story Use
- A pretty standard monster for most fRPGs, made less challenging by the fact that most PCs seem to have heard of the legend of the hydra (although the growth in general ignorance may help to counteract this) and go after them with bludgeoning weapons and piercing weapons rather than chopping bits off.
- A giant "real life" hydra would probably make a (fairly lame) monster for a (fairly camp) sci-fir horror or wierd science game.
- But funny if they are told to expect a "giant hydra" and go in mob-handed to face a jellyfish, with or without cinematic regeneration.
- The legend of the lernaean hydra and its toxic waste legacy makes a good model for beasts of legend in a fairly high fantasy RPG. White Wolf Publishing's Scarred Lands setting is virtually made of this.