in one telling , the hydra has as many as 50 heads , though several depictions show it with far fewer .
such cases could well have ? '
often , such offspring do n't just have two - headed creatures in his lab .
scientists have documented rare cases of two - headed specimens for many years .
the multi - headed lernaean hydra , a fearsome , serpent - like creature , emerged from its lair and bore down on a waiting heracles , the son of the greek god zeus .
the following year , a two - headed dolphin washed up on a turkish beach .
all the while the hydra hissed and writhed , its poisonous blood and breath threatening to exterminate greece 's greatest hero .
the monster 's final head was at last amputated and a victorious heracles was able to progress to the third of his twelve labours .
earlier , he had realised that the hydra would regrow any head that was chopped off , so he had enlisted the help of his nephew iolaus .