Editing Manannán mac Lir (section)

=== O'Donnell's Kern ===
In the story "O'Donnell's Kern", Manannan appears as a kern or serving man at the courts of various historical personages from 16th Century Ireland. As a kern, Manannan is repeatedly described as wearing thinly striped clothing and leather brogues (shoes) soaking with water, having ears and half his sword protruding from his mantle, and carrying three scorched holly javelins (elsewhere described as a single javelin) in his right hand. In this guise, he again appears as a trickster, walking into his hosts' homes uninvited and undetected by the guardsmen.

At Black Hugh O'Donnell's home in Ballyshannon, Manannan challenges the court musicians to a competition, and with a harp plays music so sweetly melodious that it can put anyone to sleep – including the suffering and dying. O'Donnell declares he has never heard such beautiful music and offers the kern new clothing; the kern refuses O'Donnell's gift and also refuses to stay in his court (indicating he must go to Cnoc Aine the next day), so O'Donnell has his men surround the kern to prevent his departure. Manannan again plays music, but this time the strain causes O'Donnell's men to hack each other to pieces with axes. When he leaves O'Donnell, Manannan extracts a fine of twenty cattle and land, and in exchange, rubs a magic herb on the gums of O'Donnell's slaughtered men that revives them to life.

At the kern's next stop near Limerick, Shane Mac an Iarla invites the kern into his home, having heard of Manannan's reputation with reading and music, to which Manannan declares he is not impotent. However, when Shane brings the kern an instrument and a book, the kern is unable to read or play until Shane lampoons him. When Shane asks Manannan whether he has visited Desmond before, he declares that he was there with the Fianna, several millennia earlier.

Next, the kern travels to Leinster to visit MacEochaidh, who is incapacitated with a broken leg and blood poisoning. When asked about his art, the kern declares that he is a healer and tells MacEochaidh that if he will put his stingy, churlish behavior past him he would be healed. Manannan then dresses MacEochaidh's leg with a healing herb, who immediately recovers from his affliction. MacEochaidh then throws a feast for Manannan and offers him his buxom daughter along with three hundred each of cattle, horses, sheep, and hogs. Before he can receive his reward, however, the kern flees MacEochaidh's house to his next destination.

He goes to Sligo where he encounters O'Conner, who is about to make war with Munster. After some ridicule from O'Conner's men, the kern offers his military services to O'Conner if he agrees that nothing unfair will be done to the kern. O'Conner's men engage in cattle raiding, and when the men of Munster attempt to steal them back, Manannan kills them with a bow and 24 arrows. He then drives all the cattle across the Shannon and back to O'Conner in Sligo. At a feast to celebrate the victory, O'Conner slights Manannan by drinking the first toast without a thought to the kern, so Manannan recites some verses indicating his displeasure and then vanishes from the company.

Then, the kern goes to Teigue O'Kelly's home and describes his art as conjuring. He bluffs O'Kelly with two spurious tricks (wagging an ear and making a reed disappear), then from a bag conjures a thread that he throws into the air and fixes to a cloud, a hare, a beagle, and a dog boy. From another bag he pulls a woman, and all the characters go running up the thread into the clouds. The king remarks that something bad will happen, such as the boy ending up with the woman, and the dog eating the hare. When Manannan reels in his thread, this is indeed, exactly what the men discover has happened, and O'Kelly, in anger, beheads the dogboy. The kern then replaces the dog boy's head backward, but after O'Kelly's complaints turns it back to the right side.

Finally, the kern visits the King of Leinster, whose musicians he declares sound worse than the sledgehammer's thunder in the lowest regions of hell. The King's musicians and men then jump the kern, but each blow they make on the kern inflicts the same wound on themselves. In retaliation, the King has the kern taken out 3 times to the gallows to be hanged, but each time, they find in the kern's place one of the king's confidants at the end of the rope. The following day at sunrise, the kern returns to the king's castle and offers to heal all the men who were killed the previous day, which he revives with a healing herb.

It is only at the end of the tale that the kern is revealed as Manannan, who is offered a dish of crabapples and bonnyclabber at Shane O'Donnellan's house in Meath. As the kern, Manannan repeatedly calls himself sweet one day and bitter or sour the next and describes himself as a stroller or traveler who was born in "Ellach of the kings". He also gives the following names for himself "Duartaine O'Duartaine", "Cathal O'Cein", "Gilla de", and "Gilla Decair" during his travels. O'Donnell's Kern is an example of the folk memory of the Irish gods long after Christianization.<ref name="MacCulloch">MacCulloch, John Arnott (1916-1932) [[wikisource:The Mythology of All Races/Celtic Mythology/Chapter 4|online "Chapter 4: Mythic Powers of the Gods"]] in ''The Mythology of All Races''.</ref><ref>[https://web.archive.org/web/20170829111719/http://www.sscnet.ucla.edu/polisci/faculty/boneill/index_files/kern.html ''O'Donnell's Kern'']</ref>