Oiche Samhain and Mag Mell
Oiche Samhain is a sacred time for the Celts. More commonly known as Halloween or the November Night, as darkness falls on the final day of October the gateway between Mag Mell or the Otherworld opens, making it easier for Spirits, Fairies, and Demons to crossover and return to the real world for one night.
The Celts would make sacrifices on Oíche Samhain, praying for prosperity in the coming year. The gods could hear these prayers more easily and celebrations often lasted for several days. In the hope of appeasing these otherworldly spirits animals would be slaughtered and food would be left out at night as tokens of appreciation. However, some spirits cared little for the desires of men, and they would return from Mag Mell for the sole purpose of wreaking havoc.
The most infamous of these was Aillen Mac Midhna. Each year on Oiche Samhain, Aillen would cross over and emerge into the real world from a cave deep in the Cooley Mountains, north of Tara.
He was a small and skinny creature, no larger than a thirteen or fourteen-year-old boy. His skin was black, charred like coal. For twenty-three years, he would make his way under the cover of darkness to Slaibh Rua or the Red Hill next to the main living quarters of the city. He carried with him a Timpan, an ancient musical instrument. A Timpan has a small drum at its base with a short neck extending out. It looks like a banjo but plays more like a fiddle or harp. Eight strings ran along the body which were tightened using pins at the tip of the neck. Aillen also carried a bow, which he moved along the strings to play music; using his other hand he could manipulate the sound by pressing down on the strings along the bridge.
He began by softly drawing his bow back and forth. Slow and steady from frog to tip and back again. As he did so the drum would vibrate and a high-pitched sound burst out in the direction of Tara. It would ripple across the city like a wave of terror; people would run for cover as soon as they heard his music. The Fianna guards understood their duty, with weapons in hand they rushed through the gate, charging in their hundreds up the Red Hill. If they could take the head of a demon, it would ensure they lived on forever, as a legend told throughout the land.
However, Aillen's melody would steadily become faster and faster, growing more mesmerizing with each note. The men would fight the music, shaking their heads and putting their fingers in their ears as they climbed up the hill; others used shields to try to block the sound waves. Alas, all their efforts were in vein; guards would drop to the ground as the enchanting tones reached their mark. One or two at first, dropping cold, falling into a deep sleep. Then a few more, and so forth until even the bravest and fiercest warriors succumbed to Aillen's Magic. All the men would lay scattered along the hillside as Aillen struck his final note. Tara was once again defenseless. Placing his Timpan and bow on the ground he would stand facing the capital. Now he could take his revenge.
The guards who were lucky enough to wake, found a burning city in chaos at their backs and the charred remains of their comrades on either side. Aillen was gone, for another year at least.