three undead horsemen who are messengers of Donn, god of the dead. The Boyhood Deeds of Fionn tells how each Samhain the men of Ireland went to woo a beautiful maiden who lives in the fairy mound on Brí Eile (Croghan Hill). It says that each year someone would be killed "to mark the occasion", by persons unknown. Some academics suggest that these tales recall human sacrifice, and argue that several ancient Irish bog bodies (such as Old Croghan Man) appear to have been kings who were ritually killed, some of them around the time of Samhain. In the Echtra Neraí ('The Adventure of Nera'), King Ailill of Connacht sets his retinue a test of bravery on Samhain night. He offers a prize to whoever can make it to a gallows and tie a band around a hanged man's ankle. Each challenger is thwarted by demons and runs back to the king's hall in fear. However, Nera succeeds, and the dead man then asks for a drink. Nera carries him on his back and they stop at three houses. They enter the third, where the dead man drinks and spits it on the householders, killing them. Returning, Nera sees a fairy host burning the king's hall and slaughtering those inside. He follows the host through a portal into the Otherworld. Nera learns that what he saw was only a vision of what will happen the next Samhain unless something is done. He is able to return to the hall and warns the king. The tale Aided Chrimthainn maic Fidaig ('The Killing of Crimthann mac Fidaig') tells how Mongfind kills her brother, king Crimthann of Munster, so that one of her sons might become king. Mongfind offers Crimthann a poisoned drink at a feast, but he asks her to drink from it first. Having no other choice but to drink the poison, she dies on Samhain eve. The Middle Irish writer notes that Samhain is also called Féile Moingfhinne (the Festival of Mongfind or Mongfhionn), and that "women and the rabble make petitions to her" at Samhain. Many other events in Irish mythology happen or begin on Samhain. The invasion of Ulster that makes up the main action of the Táin Bó Cúailnge ('Cattle Raid of Cooley') begins on Samhain. As cattle-raiding typically was a summer activity, the invasion during this off-season surprised the Ulstermen. The Second Battle of Magh Tuireadh