The Modron Procession
Location: Outlands and the Great Ring
Every 289 years—or sometimes less—a vast army of modrons pour out of Mechanus and through the gate of Automata. Mostly low-ranking modrons, the spherical monodrones and twisting boxy duodrones, but directed by a heirarchy of more complex modrons, the Procession follows an orderly clockwise path around the Great Road. As they reach the next gate-town (starting with Fortitude) they pile through the gate into the connecting plane, and then continue the procession through Arcadia and then into Mount Celestia, before coming back through the gate-town and arriving in Excelsior, in the Brinklands. This pattern continues, with the modrons passing through each of the first layers of each plane of the Great Ring, and through much of the Outlands.
The obvious question is ‘why’? And the obvious answer is ‘nobody knows, cutter’. The majority of modrons in the procession are damaged or killed along the way, although their quintescence apparently makes it back to Mechanus anyway where they can be repaired or reborn. By the end of the March, vanishingly small numbers remain, and some years no modrons make it back. While passing through each plane the little cutters do seem to be observing and making notes, although their interactions with local folks are limited. When asked what their purpose is, the question seems to puzzle the modrons, and the only answer you’ll get is something about calibrating the gears of Mechanus. But to what end, that’s dark.
It should go without saying that attacking a vast army of unfeeling modrons is a terrible idea, so most bashers take a step back and try and keep out of their way. Watching the Procession go past is quite a sight, and can take many hours, at least at the start of the event, before the modrons start to feel the attrition of passing through the Planes of Chaos and the Lower Planes last of all.
Canonical Source: The Great Modron March [2e] (adventure set during the time of the most recent Procession)
Source: Jon Winter-Holt
