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The creation myth of the Glain Neidr was specific, detailed, and utterly strange. According to Celtic tradition preserved in fragmentary texts and folklore, serpents—ordinary snakes, not supernatural creatures—would gather at particular times, most commonly on Midsummer Eve, in remote locations away from human habitation. The gathering was instinctive, driven by forces the serpents themselves did not understand, responding to lunar cycles, seasonal transitions, perhaps magnetic or telluric currents humans could not perceive.
Once assembled, the serpents would intertwine, forming great writhing masses of scaled bodies, dozens or hundreds of individuals creating temporary super-organism. The intertwining was not mating—this was something else, a ritual or natural process unique to these gatherings. As the serpents twisted together, they secreted substances—saliva, venom, perhaps other bodily fluids—that mixed, congealed, began to solidify.
The mass of secretions would gradually form into sphere or egg-shape, the serpents’ continued motion polishing its surface, their combined body heat accelerating the solidification process. As dawn approached—the critical moment—the Glain Neidr would be complete, a smooth, hard object the size of a hen’s egg or sometimes larger, often exhibiting peculiar patterns, colors, or translucency.
But the serpents would not willingly surrender their creation. The moment the egg was complete, they would attempt to destroy it or hide it, driven by same instinct that created it to now protect or eliminate it. The human seeking Glain Neidr had narrow window—between egg’s completion and serpents’ destruction of it—to claim the prize.
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