Magical Items that could destroy a City

[ErebusVonMori]

What magical items could be used to cause serious damage to a city? e.g a slime pot emptied onto the main grain storage or a decanter of endless water buried beneath the city

[Braininthejar2]

A holy arrow. knock 1 level off a first non-good commoner that picks it up, and start a wightocalypse.

[Gildedragon]

A sphere of annihilation: obvious having it tunnel underground undermining the city is particularly evil
A lyre of building: "Oh dear... I used the rocks of all ya'lls' walls to build this tower?"

[ErebusVonMori]

Preferably something a little cheap than a sphere of annihilation. And pretty sure incorporeal undead won't be allowed. What about ring gates? Dump one in an ocean?

[The_Jette]

Armor of rage: anyone who puts it on is the target of everyone else's hatred. Slowly, the town kills off all of its guard, then is left defenseless.
Flask of Curses: Sent to the local tavern, and unstoppered during the evening meal. All of a sudden, half the town is cursed.
Book of Perilous Journeys: Call down different monsters to attack your town at night. Also, might screw with the local weather.

In all honesty, there are a lot of cursed items that can cause ruin to a town. I remember a cursed item that its only power was to cause people who look at it to want it. The more they were around it, the stronger the desire. Eventually, people were murdering each other over possession of it. And, it was a useless bauble.

[Gildedragon]

Preferably something a little cheap than a sphere of annihilation. And pretty sure incorporeal undead won't be allowed. What about ring gates? Dump one in an ocean?

Ring gates have a volume limit.

Enough dust of sneezing and choking would work.

Darksand

[evedgebah]

Portable Hole + Bag of Holding.

Mishap with Scroll of Gate (or any high level spell really).

[MesiDoomstalker]

Preferably something a little cheap than a sphere of annihilation. And pretty sure incorporeal undead won't be allowed. What about ring gates? Dump one in an ocean?

Wight's aren't Incorporeal Undead. They are corporeal and anything that dies from having too many Negative Levels comes back as a Wight (some special cases apply, depending on how the Negative Levels were gained). Wights give Negative Levels with each of their attacks and are hostile, so all it takes is the first Non-Good, level 1 NPC to pick up the Arrow to create 1 Wight and then that 1 Wight to touch at least 1, 1-HD person to start a chain reaction.

[Coidzor]

Eversoaking Sponge and their water supply going bye-bye can cause some problems.

[MesiDoomstalker]

I forget which Ooze it is, but there's an Ooze which grows rapidly when subject to Fire. With no limits, so if you keep applying fire, one can cover the entire city in the Ooze.

[Gildedragon]

brown mold to freeze the city...

[unseenmage]

Mirror of Opposition in the town square.

Creative custom items of War spells.

A really big golem (in games where the 'Constructs are Magic Items' rules interpretation is in effect.

An innocuously shaped Intelligent Magic Item with a decent Ego score whose purpose is to destroy the settlement.

A well hidden resetting Magic Trap of Plane Shift in an oft travelled dark alley.

Orb of Weather Control.

Orb of Dragonkind, just leave it lying about. Destruction should come calling soon enough.

A Deck of Many Things. As above. Be sure to bring popcorn.

A Staff of Animate Objects at a high enough CL to make the buildings fight each other.

[Âmesang]

THE BRINGER OF DOOM

The Bringer of Doom

So distant in the past is the Age of Doom that it cannot even be conceived of by mortals. This was a time of great lamenting, for the beings of that age had discovered magic and sciences too powerful to handle. Their passions overcame their sense and, in a wave of power, the race destroyed itself, leaving behind no remnant, save one.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifThe Bringer of Doom is a small box with a strange, circular red gem set in its lid. If the gem is touched and depressed, the box itself explodes in a blinding flash. So great is the force of the blast that everything within 100 feet (including the user and the item itself) is destroyed utterly.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifThe explosion opens a temporary one-way rift to the Gray Waste of Hades from which 100d10 horldings pour forth and destroy everything they encounter. Rarely (10% chance) some other, greater fiend comes through the rift as well. The Bring of Doom always reforms, to be discovered some time later.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifOne account of the Bringer comes from a scrap of parchment found in the Desert of Yin, near the blasted tower of the evil mage Althabazzerid:
https://www.schadenfreudestudios.com/backup/pictures/indent.gif"We have set up magical circles of protection, but we don't know how long we can keep them up. I hope that my observations may be of help to my fellow researchers of the Mages' Guild of MakBran. The assault against the black tower went well, the elven archers easily destroying Althabazzerid's undead army while we dealt with his dragon allies. We had closed in and were in the midst of magical combat when Althabazzerid himself appeared on the tower's battlements, protected by a multicolored sphere of light. He raised a small box in his left hand, and perhaps pressed a button on it—hard to tell from our vantage point."

https://www.schadenfreudestudios.com/backup/pictures/indent.gif"At once there was a deafening blast, and the wizard and his tower were destroyed. A huge hole in space opened, and we could see into the dismal spaces of the Gray Wastes. A great crowd of horrid beings—a more fantastic mix of humans, beasts, and fiends cannot be imagined—began moving into our world. Some walked, some hopped, some dragged their deformed bodies along. They gibbered and screamed. Some spat fire, or gas, or acid. Some were horned, others bore tentacles. More and more came, destroying the elves by sheer press of numbers. They attacked without plan or strategy, yet their horrid deformations allowed them many advantages."

https://www.schadenfreudestudios.com/backup/pictures/indent.gif"Then a great fiend flew out from the darkened sky of the Gray Wastes. It has assaulted unceasingly since then. Soon our magics will fail, and we will die either at the hands of the fiend or the press of the horde of darkness…"
— PLANESCAPE® Monstrous Compendium Appendix, p.55

Hordling (Hordes of Hades)

Hordlings are the uncounted hordes of the Gray Wastes. They form the majority of the population of that plane. They vary widely in size and appearance. Some are large, some small; some humanoid, some animal-like, some amorphous; some have wings or tentacles. No two look exactly alike, and they have no standard means of communication.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifHabitat/Society: There are an infinite number of hordlings on the infinite layers of the Abyss. They have no purpose or organization.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifHordlings are petty and vile. They roam the Gray Waste, attacking those weaker than themselves. They sometimes serve under strong leaders, but few leaders maintain hordlings for long, for they are unruly, untrustworthy, and chaotic.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifOccasionally, evil mages summon hordlings to do their bidding. Normal summonings always produce a single hordling. The only known way to summon more than a single hordling into the Material Plane is the Bringer of Doom, a strange device created by arcane magic during the Age of Doom.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifEcology: Hordling's devour whatever they destroy, usually other hordlings. That there is otherwise no readily available food supply on the Lower Planes makes the endless, relatively weak hordlings common prey for more powerful beings.
— PLANESCAPE® Monstrous Compendium Appendix, p.54

The Path of History

https://www.schadenfreudestudios.com/backup/pictures/indent.gifThe root cause of the animosity between the Suel Imperium and the Baklunish Empire is lost in time, but the end result of their final war haunts even the modern day. After decades of conflict, the Suloise Mages of Power called down the Invoked Devastation upon the Baklunish, resulting in an apocalypse so complete that its true form remains unknown. Entire cities and countless people were purged from Oerth, leaving few signs of the great civilization that thrived from the Sulhaut Mountains to the Dramidj Ocean.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifIn retaliation, a cadre of Baklunish wizard-clerics, gathered in the great protective stone circles known as Tovag Baragu, brought the Rain of Colorless Fire upon their hated enemies. The skies above the Suel Imperium opened, and all beings and things beneath this shining rift in the heavens were burned into ash. So terribly did these attacks plague the world that they have come to be called the Twin Cataclysms, a term understood by nearly every resident of the Flanaess. The Dry Steppes and Sea of Dust are geographical reminders of this unbridled magical power, now lost to all people—perhaps for the better.
— LIVING GREYHAWK™ Gazetter, p.13

Room of Mercy

https://www.schadenfreudestudios.com/backup/pictures/indent.gif"Who are you? Where are you? What are you? Why are you? Who am I? Where am I? What am I? Why am I?" The whispers repeat the same words endlessly, sometimes in the same archaic dialect, other times in Ancient Suloise. In the center of a room, levitating in mid-air, apparently untouched by dust, is a three-inch-square black cube, apparently made from malachite.

https://www.schadenfreudestudios.com/backup/pictures/indent.gifThe cube is the prison for Zol Darklock, a Power of Shadow (NE male shade fighter 1/sorcerer 6/eldritch knight 10/shadow adept 4). If greater dispel magic is successfully cast against the cube (DC 34), then the entity will be released. Zol was a shadow prince who also lived for a time as a noble of the Suel Imperium. He was trying to investigate a rumor about Xodast, a Suel Mage of Power who experimented with powers that most said were better left undisturbed. Xodast, it was said, had created the Bringer of Doom, an artifact that later played some part in the Invoked Devastation that destroyed the Baklunish Empire (which would not occur for two centuries after Zol's imprisonment). Xodast imprisoned Zol in "The Darkness That Holds All Shadows" (the cube), which was found shortly after the Rain of Colorless Fire by a group of adventurers exploring the ruins of the Suel city Suendrako.
— Castle Greyhawk, p.97

The Lost Laboratory

This cairn, the convergence of the two great lines of force on which the other cairns were built, was used to research powerful and terrible new spells. The magical focus was so strong in this place that not only were all spells cast here hard to resist, but magic charged the very minds of wizards who stayed here, allowing them to cast more spells than they were normally able. There were no locks on any of the doors—the servants were all charmed slaves and the wizards saw no need to set up any sort of security other than the capstone on the top level.

Two of the most powerful wizards involved in this project were researching ways to recreate the Twin Cataclysms that destroyed the Suel and Bakluni empires; their hope was to find a more controlled way of decimating a large number of opponents. One, a woman named Alatla Minah, explored the invocation of pure elemental matter, thinking to emulate the Rain of Colorless Fire. The other, a man known as The Longsword for his unusual ability to fight with that weapon, studied the means to open a gate to the lower planes and unleash a fiendish horde, inspired by a similar event which occurred during the Invoked Devastation due to the mysterious Bringer of Doom. A third wizard, a quiet man called Titianus Cremul, worked on spells to hide and move entire armies. During a critical point in their research, the first two wizards tested their findings simultaneously, creating an overlapping effect that interacted with the coincidental crash of the meteor in the Abbor-Alz; the cairn and all of its inhabitants were pulled into a juncture between the Astral, Ethereal, and Material planes. The demon-summoning spell partly succeeded, trapping a glabrezu demon (or tanar'ri) within the cairn. The other inhabitants of the cairn have either been killed or changed due to their exposure to the other planes. The magical lights continue to function here, providing illumination for all of its strange residents. As the cairn is no longer above the Oerthly ley-line, the magical enhancement that made this place so valuable is no longer in effect; the two lines have altered a bit over time and no longer complement each other, making the actual site on Oerth nothing special.
— The Star Cairns, p.38

Thus Spake Gary Gygax: Ye Secrets of Oerth Revealed

Q: The Rain of Colorless Fire's effects are detailed by you in the 1983 World of Greyhawk boxed set and earlier folio:


"…in return for the terrible magical attack [the Invoked Devastation], the Suloise lands were inundated by a nearly invisible fiery rain which killed all creatures it struck, burned all living things, ignited the landscape with colorless flame, and burned the very hills themselves into ash."

The Invoked Devastation, on the other hand, is a little more vague — are its effects a massive, instantaneous disintegration? Or is it a rapid erosion, crumbling the Baklunish Empire in a sudden sweep of time — an unmaking of things? Are there ruins left behind? Dead bodies? What are the effects on the landscape?

A: Here we have it, a very sound guess, all of which are correct, as I envisioned the effect. A wave of something sweeps over the land. Buildings begin to crumble as if being powdered by an oerthquake, only the ground is not shaking. All living things within the area are sickened. Although some survive, most others are less fortunate. The wind is black and howling, and under its strange force the work of the hands of man decays as if time were running a thousand times faster for such non-living matter. Living things suffer increased aging, but not so severely. Trees grow suddenly, deplete their soil, and die. Animals age and die. Children become adults, but, lacking the nutrients for growth, die. A handful of the young adult folk escape as near- and middle-aged wrecks. The remains of the dead are visible for some period, but the habitations are naught but powder and dirt. It is a desolate place that only time will restore. In a score of years, though, the whole is covered by weeds and struggling plants, and slowly, as the bacteria and worms and insects make their way into the soil, the land becomes a wilderness that can support normal life again.
— Oerth Journal #12, p.5

[Braininthejar2]

custom coin of contagion.

[Gildedragon]

Depending on the city: Dust of Dryness into the nuclear power plant
Too dark?