3d10 Mechanus Encounters

tl;dr: things you can run into on the move in Mechanus. Tends more towards chaotic than the sites because they keep on the move.

Inspired by the old Monstrous Compendium II, the 3.5e Manual of the Planes and boosted by a sweep up of creatures that are lawful. Use these as the wandering component between hinter-cog sites described previously.

Roll 3d10
3. Modron Heirarch (d100 - 1-38 Decaton Administrator, 39-68 Nonaton Arbiter, 69-86 Septon Inspector, 87-100 Hexton General) - will always appear with a task group of minor Modrons - Pentadrones, Quadrones, Tridrones, Duodrones and Monodrones - to help them do what they need.
4. Were-creatures* - lawful ones like werebears, tied to moons of a prime somewhere.
5. Aasimar* from (d12 - 1-3. Arcadia 4-5. Mount Celestia 6-7. Bytopia 8-9. Elysium 10. the Beastlands, 11. Arborea, 12. Ysgard)
6. Hobgoblins* of Acheron
7. Bladeling* of Acheron
8. Undead - a guard force set in place by someone long gone, compelled to remain by the Laws of Mechanus. They will attack relentlessly hoping for destruction and rest at last.
9. Abeil - a scouting and foraging party from a nearby hive, mostly workers but attack will lead to rapid reinforcement with soldier abeil
10. Modron Pentadrone - a small of Pentadrones on an inspection tour of recent Modron works in the area.
11. Gear Spirit - hiding from Modrons
12. Quill/Leomarh - day time finds the Quill foraging, night finds the Leomarh on the hunt
13. Modron Quadrone - a repair patrol, will interrogate any strangers they encounter to find out what they have broken so they can go fix it. Strangers always break things, it is known.
14. Petitioners* of Mechanus
15. Modron Tridrone - dangerous animal patrol with crew of duodrones and monodrones; nets, mancatchers and cages are present. They will attempt to capture any large animal (including adventurers) they find, to bring back for tagging and release into a reserve
16. Tso - 1 in 6 these spider-eel horrors have successfully rounded up captives and are guarding a pen waiting for their ship to return, otherwise they are skulking about looking for victims to capture alive
17. Modron Duodrone - carrying around a device that warns strangers to abide by local regulations, operates by winding handle. Will play the device at each individual stranger it encounters before going hunting for more strangers.
18. Modron Monodrone - a work crew marching from site to site carrying an array of construction tools. Will continue on task of 'go to this site' until instructed otherwise by a Duodrone.
19. Reave* of the Outlands
20. Merkhant - 2 in 6 have set up shop hoping for trade, otherwise are a caravan with guards
21. Formians - scouting for new hive sites, will attempt to claim anything valuable for their hive such as carried treasure. Will back off a sufficiently hostile response.
22. Arcane - always appears as a trade caravan with guards.
23. Inevitables - en route to a portal to hunt a transgressor against the divine. Will run over anything that gets in front of them, will slay anything that interferes with them.
24. Demarax - 1 in 6 chance of actively chasing a spell crystal otherwise this big blue spell-gem eating crocodile is just lying about on its belly
25. Observer - off its patch and in full data gathering mode. Supremely confident in itself, may shadow interesting things for a while. Will laugh at any misfortune that befalls in its sight.
26. Githzerai*
27. Sand Giants - hunting for interesting sands ground from the edges of the turning gears. These are delicacies for them.
28. Tieflings* from (d12 - 1-3. Acheron 4-6. the Nine Hells 7-8. Gehenna 9. Gray Waste 10-11. the Abyss, 12. Pandemonium)
29. Gem Dragon - admiring itself in a large reflective crystal, will demand its rightful tribute, a 1 in 10 tithe of treasure carried, pursuant to section 25 of the Laws of Mechanus. This does actually exist but section 25 is wholly voluntary and in fact says that dragons may only take up to a tenth of travellers treasure or the Modrons will hunt them.
30. Androsphynx - surveying the turning of the gears, looking for somewhere to take some measurements. Will be happy to talk but will react badly to chaotic behaviour that disturbs its serenity.

For anything with a * roll d4 below to see what this group is. Otherwise assume a local or monster wandering about away from its lair.

1. Adventurers - this bunch is from off-plane, travelling through Mechanus. Their arms and equipment will clearly identify them as outsiders and their plane of origin. Will be better disposed to other outsiders than pure alignment might suggest as they have not been enjoying their trip so far.
2. Pilgrims - primes come to Mechanus seeking the realm of their God (d4 1. Ptah, 2. Janus, 3. Erathis, 4. Lendor) - they are excited and will ask directions.
3. Trade Caravan + Guards - an aggravated merchant and surly guards watch irritated drovers and heavily laden donkeys. Getting all the caravan from cog to cog has been a long, painful process. Cursing this plane as an icebreaker will get you a surprisingly warm welcome
4. Scouts - a light, loose group on the outbound leg of their mission. In good cheer and willing to trade advice or knowledge like for like.

You can see the heirarchy of Modrons at this link.