they were descended from the god
came to Ireland from his kingdom in the Spirit world on Beltane or May
day. For many years he fought with the Fomhóire who were a race of
Mythology says that the Fomhóire (or Fomorians) had the heads of goats and bulls, and a single hideous eye. They were the ancestors of the giants and leprecauns, and their evil race was eventually defeated in the second battle of Magh Tuireadh by an alliance of gods and spirits.
After their exile from Ireland the Fomorians transformed themselves into sea monsters.