CITY HAZARDS

As with any other terrain, the urban environment has its own dangers. Some are obvious and easy to avoid, at least for natives, while others can trap or harm even the most wary individuals.

NATURAL HAZARDS

In addition to the hazards presented below, a city’s road conditions and level of sanitation might increase the danger.

Decrepit Buildings: Old, abandoned buildings can come down with dangerous ease. Weakened by age and weather, they have half the normal hardness of their component material. An attack or an area spell inside such a building deals damage to the structure more easily. Whenever a decrepit building takes damage, roll 1d20: If the result is at least equal to the damage dealt, the building collapses. Anyone inside a collapsing building takes 1d8 points of bludgeoning damage for each floor of the building’s height (assuming 10 feet of height for each story of the structure) and is pinned beneath the rubble. A successful DC 15 Reflex save halves the damage and avoids the pin. A character can escape the pin with a successful DC 24 grapple or Escape Artist check. Each round a character remains pinned, he takes an additional 1d6 points of damage.

Lamp Smoke: In cities that use oil lamps for illumination, smoke can accumulate in small alleys or narrow roads. The smoke causes eyes to water, and obscures vision, but doesn’t provide concealment. Creatures inside the smoke take a –2 penalty on attack rolls, as well as on Search and Spot checks.

Plague Animals: Much of a city’s wildlife feeds on garbage or dwells in the sewers, exposing the creatures to disease. Any feral animal encountered in a city has a base 10% chance of being a disease carrier. If the city has only drainage ditches to deal with waste, this chance increases to 20%; if the city has no waste disposal system at all, it rises to 40%. If an animal is a carrier, anyone it injures is susceptible to filth fever (Fortitude DC 12 negates). This save is in addition to any that might be required due to unsanitary conditions.

Potholes: Even on well-kept roads, cobblestones occasionally crack, or packed earth sinks, forming potentially hazardous potholes. A small pothole (1 foot or less in diameter) requires a successful DC 15 Spot check to notice. Any creature moving on land across an undetected small pothole must succeed on a DC 10 Refl ex save or fall prone, taking 1d4 points of nonlethal damage. A small pothole does not harm a wagon or carriage, but the Concentration DC to cast spells while moving over it increases by 5.

Large potholes (2 to 3 feet in diameter) are easier to detect, requiring only a DC 10 Spot check. Any creature moving on land across an undetected large pothole must succeed on a DC 15 Reflex save or fall prone, taking 2 points of Dexterity damage and a –5 penalty on any land-based movement rate, due to leg injury. The driver of a carriage or wagon that moves into a large pothole must succeed on a DC 15 Handle Animal or Profession (teamster) check. On a failure, the vehicle’s wheels and axles are damaged, requiring 1d20 hours and the appropriate Craft skill to repair.

Sinkholes: Due to hollows in the earth or erosion from heavy rains, sections of land might collapse entirely. A slow sinkhole is comparable to quicksand (DMG 88), while a sudden sinkhole is treated as a 20-foot-deep (or even deeper) pit trap that cannot be reset.

MAGICAL HAZARDS

The prevalence of magic in a fantasy city produces unnatural dangers unique to that environment.

Alchemical Fog: Alchemical and magical experimentation and item creation frequently involve burning and boiling various substances. On dry, windless days, the fumes released by these processes accumulate in pockets of alchemical fog. A fog might cover only a single building or city block, or it might spread across entire districts.

A creature that enters an alchemical fog must attempt a DC 12 Fortitude save, with an additional save every 24 hours spent within the fog. Success means no physical impairment other than an annoying cough. On a failure, the creature is sickened for 24 hours. If a creature is sickened by the fog for a number of consecutive days equal to its Constitution modifi er (minimum 1), it takes 1d2 points of Constitution damage each consecutive day it remains sickened.

An alchemical fog can last for days or, rarely, weeks or months. Roll 1d10: On a result of 1–9, the fog remains for that many days. On a result of 10, roll again and add that result to 10. (Continue rerolling as long as the die keeps coming up 10.) The fog’s duration also depends on if the weather remains dry and calm. Should a strong wind arise or a storm blow in, the fog dissipates regardless of the predetermined duration.

Alchemical Rain: Sometimes the fumes that create an alchemical fog rise into the upper atmosphere, resulting in alchemical rain. The first rain after an alchemical fog is dispersed is usually an alchemical rain, but such a phenomenon can occur without warning. The dissolved substances in alchemical rain are highly caustic: Any creature or object caught in an alchemical rain takes 1 point of damage per round on a cumulative basis—1 point of damage in the first round, 2 points in the second, 3 points in the third, and so forth. Thus, a lengthy alchemical rain can eventually damage even objects that have reasonably high hardness.

Alchemical rains are usually brief, but sometimes can last for several minutes. Roll 1d10: On a result of 1–9, the rain falls for that many rounds. On a result of 10, roll again and add that result to 10. (Continue rerolling as long as the die keeps coming up 10.)

Arcane Pollution (CR 5): Arcane pollution is a rare phenomenon that occurs in and near wizards’ colleges and arcane laboratories. In a 60-foot radius around a central point, the atmosphere is tainted by magical residue and the effluvia of arcane experiments, producing random spell effects. A creature entering an area of arcane pollution must succeed on a DC 17 Fortitude save to avoid its effects. On a failure, roll 1d20 and consult the following table; the creature is targeted by the listed effect.

Arcane Pollution Effects

d20	Spell Effect*
1	Baleful polymorph (up to Small animal or Small vermin only)
2-3	Gain spell resistance 14 for 4d20 minutes
4-6	Change to random color for 4d20 minutes
7-9	Confusion
10–11	Deep slumber
12	Targeted dispel magic
13	Displacement
14	Enervation
15	Enlarge person
16	Haste
17	Hold person
18	Reduce person
19	Slow
20	Teleport (1d10 miles, random direction)

* If a spell effect requires a saving throw, the DC is 13 + spell level. Each spell has a default caster level of 10th.

An antimagic field suppresses the effect of arcane pollution. Arcane pollution can be destroyed with a successful dispel magic check (DC 10 + the level of the spell effect). Unless the pollution is suppressed or destroyed, it remains in place permanently.

Black Mold (CR 4): Black mold is an insidious substance that can produce citywide epidemics without any readily apparent source. Black mold can appear anywhere within 1 mile of a major source of magical energy or alchemical fumes—in other words, almost anywhere in a city. This mold usually grows in 5-foot-square patches. It favors corners and shadowy areas, requiring a successful DC 15 Search or Spot check to detect. Living creatures within 30 feet of black mold must succeed on a DC 14 Fortitude save or contract mindfi re (DMG 292). They must repeat this save for every 24 hours of exposure, even if the fi rst save was successful. Physical contact with black mold deals 1d4 points of Intelligence damage as well as requiring a save to avoid the disease. Direct sunlight renders black mold dormant. Fire and remove disease destroy it.

Necrotic Miasma (CR 3+): Sometimes a city’s magical residue combines with the psychic anguish of the victims of violent crimes. This necrotic miasma lingers in an alleyway or building, causing the area or structure itself to consume life energy. Such locations are often the source of local haunting tales, because undead tend to congregate there.

A living creature takes 1d6 points of damage every round when it is inside a building or an area tainted by necrotic miasma. A successful DC 12 Fortitude save halves this damage; this save must be repeated in each round that exposure continues. Damage can manifest as a feeling of weakness and pain, or wounds might open on the subject’s fl esh. This is a necromantic death effect, and is thwarted by death ward and similar protections. Undead in the area benefi t as from the effect of a desecrate spell.

A consecrate spell suppresses the effect of necrotic miasma, and hallow removes the hazard entirely. Nothing else works; even if an affected structure is destroyed, the necrotic miasma still lingers in the area.