Via shapeshifting, people, and more particularly gods and goddesses, were able to change into animals, and vice versa. People were also able to transform their own appearance deliberately, for example warriors pulled grotesque faces to make themselves more frightening in battle. The Celts took this to extremes. The description in the Irish folk-tale the Tam ho Cualnge may exaggerate, but it gives an idea of what warriors were trying to achieve. The hero Cii Cnchlainn mounted his scythed battle chariot:
Then took place the first twisting fit and rage of the royal hero Cu Chulainn, so that he made a terrible, many-shaped, wonderful, unheard-of thing of himself His flesh trembled about him like a pole against the torrent or like a bulrush against the stream... He made a mad whirling-feat of his body inside his hide... He gulped down one eye into his head so that it would be hard work if a wild crane succeeded in drawing it out to the middle of his cheek from the rear of his skull... The Hero’s Light stood out on his forehead, so that it was as long and as thick as a warrior’s whetstone, till he got furious handling the shields, thrusting out the charioteer, destroying the hosts... When now this contortion had been completed in Cu Chulainn then the hero of valour sprang into his scythed war chariot with its iron sickles.
An unusual coin from north-western France shows a horse with a gigantic human head, as if the horse is turning into a god. Behind the horse god is a suggestion of a chariot and a charioteer, holding onto the monster’s reins. The gold coin was minted by the Aderci Diablintes tribe in the first century BC.
There are stories that indicate that a belief in the transmigration of sods was widespread in Wales; the departing sod went into the body of an animal (see Hare).