Zeitgeist (CR 23)

Huge Fey (Incorporeal)
Alignment: Varies
Initiative: +1(Dex); Senses: all-around vision, low-light vision, Listen +26, and Spot +30
Languages: Common, Dwarven, Elven, Gnome, Sylvan, plus one more as appropriate to the specific city; telepathy

AC: 9 (-2 size, +1 Dex), touch 9, flat-footed 8
Hit Dice: 20d6+200 (270 hp)
Fort +16, Ref +13, Will +15
Speed: Fly 60 ft. (perfect)
Space: 10 ft./15 ft.
Base Attack +10; Grapple -
Attack: Spell-like abilities
Special Attacks/Actions: urban manifestation
Abilities: Str -, Dex 13, Con 30, Int 22, Wis 16, Cha 25
Special Qualities: incorporeal traits, invisibility; fast healing 10; SR 34; Spell-Like Abilities (CL 20th): At will - animate objects, call lightning storm (DC 22), calm emotions (DC 19), confusion (DC 20), contagion (DC 20), fear (DC 20), impeding stones (DC 18), make whole, move earth, produce flame, remove disease, repel metal or stone, repel wood, soften earth and stone, spike stones (DC 21), stone shape, swarm sphere (DC 20), wall of iron, wall of stone, wood shape, zone of peace (DC 22)
Feats: Cleave, Great Cleave, Improved Bull Rush, Improved Sunder, Power Attack, Quicken Spell-Like Ability (repel metal or stone), Quicken Spell-Like Ability (repel wood),
Skills: Appraise +29, Concentration +33, Diplomacy +32, Gather Information +9, Intimidate +30, Knowledge (architecture) +29, Knowledge (history) +29, Knowledge (local) +29, Listen +26, Search +33 (+35 secret doors), Sense Motive +26, Spellcraft +29, Spot +30, and Survival +3 (+5 following tracks)
Advancement: 20-30 HD (Huge), 31-60 HD (Gargantuan)
Climate/Terrain: Any urban
Organization: None
Treasure/Possessions: None

Source: Cityscape

All-Around Vision (Ex): A Zeitgeist is a part of the city that surrounds it, so it sees from all directions at once, providing it a +4 racial bonus on Search and Spot checks. Opponents gain no benefits when flanking a Zeitgeist.

Greater Invisibility (Su): A Zeitgeist remains invisible even when it attacks. This ability is constant, but the Zeitgeist can suppress or resume it as a free action.

Urban Manifestation (Su): Once per day, a Zeitgeist can assume a form composed of smoke, of stone detritus and portions of old buildings, or even of humanoid figures. In manifested form, a Zeitgeist is no longer invisible or incorporeal. It gains the specific qualities noted under the appropriate manifestations, below, and loses the benefits of the incorporeal subtype. Should a Zeitgeist's urban manifestation be destroyed, it dissipates and must wait 24 hours before it can use any of its abilities again.

While a Zeitgeist is manifested, the following changes to its statistics are in effect: AC 19 (touch 9, flat-footed 18); Melee +14/+14 (see below for type and damage); Grp +24; DR 15/cold iron and magic; Str 22.

Mob Manifestation

A Zeitgeist can take the form of a mob of humans (page 124 of Cityscape), albeit of Huge size. It cannot make slam attacks in this form, instead making mob attacks as described in that entry. It retains its own Hit Dice, hit points, and abilities, rather than adapting those of the mob.

Smoke Manifestation

A Zeitgeist in this form appears to be an enormous cloud of semi-solid rolling smoke. In smoke form, the Zeitgeist's melee attacks are slams dealing 2d4+6 points of damage (plus fire damage, as described below). It gains the following abilities:

Air Mastery (Ex): Airborne creatures take a -1 penalty on attack and damage rolls against a Zeitgeist manifested as smoke.

Choke (Ex): In smoke form, the Zeitgeist can move into an opponent's square as though making a trample attack. The victim takes 1d4 points of damage and must make a DC 26 Fortitude save or be sickened by the choking vapors. This effect lasts as long as the creature remains within the smoke and for 1d4 rounds thereafter.

Fiery Slam (Ex): A Zeitgeist deals 1d4 points of damage with its slam attack. The heat of the smoke is not sufficient to set creatures or objects alight, however.

Subtypes (Ex): A Zeitgeist manifested as smoke gains both the air and fire subtypes.

Flight (Ex): A Zeitgeist manifested as smoke is naturally buoyant. At will as a free action, it can produce an effect like that of the fly spell (caster level 5th), except that the effect applies only to itself. This ability gives it a fly speed of 120 feet (perfect).

Stone Manifestation

A Zeitgeist taking this form appears to be a huge humanoid figure, composed of stones, detritus, and even whole buildings. In stone form, a Zeitgeist's melee attacks are two slams dealing 2d8+6 points of damage. In this form, a Zeitgeist gains the following abilities:

Earth Mastery (Ex): A Zeitgeist manifested as stone gains a +1 bonus on attack and damage rolls if both it and its foe are touching the ground. If an opponent is airborne or waterborne, the Zeitgeist takes a -4 penalty on attack and damage rolls.

Incorporeal Subtype

Some creatures are incorporeal by nature, while others (such as those that become ghosts) can acquire the incorporeal subtype. An incorporeal creature has no physical body. It can be harmed only by other incorporeal creatures, magic weapons or creatures that strike as magic weapons, and spells, spell-like abilities, or supernatural abilities. It has immunity to all nonmagical attack forms. Even when hit by spells, including touch spells or magic weapons, it has a 50% chance to ignore any damage from a corporeal source (except for positive energy, negative energy, force effects such as magic missile, or attacks made with ghost touch weapons). Non-damaging spell attacks affect incorporeal creatures normally unless they require corporeal targets to function (such as the spell implosion) or they create a corporeal effect that incorporeal creatures would normally ignore (such as a web or wall of stone spell). Although it is not a magical attack, a hit with holy water has a 50% chance of affecting an incorporeal undead creature.

An incorporeal creature's natural weapons affect both in incorporeal and corporeal targets, and pass through (ignore) corporeal natural armor, armor, and shields, although deflection bonuses and force effects (such as mage armor) work normally against it. Attacks made by an incorporeal creature with a nonmagical melee weapon have no effect on corporeal targets, and any melee attack an incorporeal creature makes with a magic weapon against a corporeal target has a 50% miss chance except for attacks it makes with a ghost touch weapon, which are made normally (no miss chance).

Any equipment worn or carried by an incorporeal creature is also incorporeal as long as it remains in the creature's possession. An object that the creature relinquishes loses its incorporeal quality (and the creature loses the ability to manipulate the object). If an incorporeal creature uses a thrown weapon or a ranged weapon, the projectile becomes corporeal as soon as it is fired and can affect a corporeal target normally (no miss chance). Magic items possessed by an incorporeal creature work normally with respect to their effects on the creature or another target. Similarly, spells cast by an incorporeal creature affect corporeal creatures normally.

An incorporeal creature has no natural armor bonus but has a deflection bonus equal to its Charisma bonus (always at least +1, even if the creature's Charisma score does not normally provide a bonus).

An incorporeal creature can enter or pass through solid object but must remain adjacent to the object's exterior, and so cannot pass entirely through an object whose space is larger than its own. It can sense the presence of creatures or objects a square adjacent to its current location, but enemies have total concealment from an incorporeal creature that is inside an object. In order to see clearly and attack normally, a incorporeal creature must emerge. An incorporeal creature inside an object has total cover, but when it attacks a creature outside the object it only has cover, so a creature outside with a readied action could strike at it as it attacks. An incorporeal creature cannot pass through a force effect.

Incorporeal creatures pass through and operate in water as easily as they do in air. Incorporeal creatures cannot fall or take falling damage. Incorporeal creature cannot make trip or grapple attacks against corporeal creatures, nor can they be tripped or grappled by such creatures. In fact, they cannot take any physical action that would move or manipulate a corporeal being or its equipment, nor are they subject to such actions. Incorporeal creatures have no weight and do not set off traps that are triggered by weight.

An incorporeal creature moves silently and cannot be heard with Listen checks if it doesn't wish to be. It has no Strength score, so its Dexterity modifier applies to both its melee attacks and its ranged attacks. Non-visual senses, such as scent and blindsight, are either ineffective or only partly effective with regard to incorporeal creatures. Incorporeal creatures have an innate sense of direction and can move at full speed even when they cannot see.