In the stories of Etain and of Lud, reborn as Setanta, this idea of divine transformation and rebirth occurs. A similar idea may underlie the tale of Fionn and Mongan. As to the tales of Gwion and the Swineherds, the latter the servants of gods, and perhaps themselves regarded once as divinities, who in their rebirth as bulls are certainly divine animals, they present some features which require further consideration. The previous transformations in both cases belong to the Transformation Combat formula of many _Märchen_, and obviously were not part of the original form of the myths. In all such _Märchen_ the antagonists are males, hence the rebirth incident could not form part of them. In the Welsh tale of Gwion and in the corresponding Taliesin poem, the ingenious fusion of the _Märchen_ formula with an existing myth of rebirth must have taken place at an early date.[1207] This is also true of _The Two Swineherds_, but in this case, since the myth told how two gods took the form of worms and were reborn of cows, the formula had to be altered. Both remain alive at the end of the combat, contrary to the usual formula, because both were males and both were reborn. The fusion is skilful, because the reborn personages preserve a remembrance of their former transformations,[1208] just as Mongan knows of his former existence as Fionn. In other cases there is no such remembrance. Etain had forgotten her former existence, and Cúchulainn does not appear to know that he is a rebirth of Lug.