Aoa Sphere (CR 15)

Huge Outsider (Extraplanar)
Alignment: Always Neutral
Initiative: +8 (+4 Dex, +4 Improved Initiative); Senses: Listen +19 and Spot +19
Languages: No language

AC: 20 (-2 size, +4 Dex, +8 natural), touch 12, flat-footed 16
Hit Dice: 13d8+91 (149 hp); DR: 10/magic
Fort +15, Ref +12, Will +13
Speed: Fly 50 ft. (perfect)
Space: 15 ft./10 ft.
Base Attack +13; Grapple +22
Attack: Slam +16 melee
Full Attack: Slam +16 melee
Damage: Slam 2d6+1/19-20
Special Attacks/Actions: Dispelling touch, reflective pulse
Abilities: Str 12, Dex 18, Con 25, Int 4, Wis 17, Cha 11
Special Qualities: outsider traits, reflective SR 25, resistances, spell-like abilities, split
Feats: Improved Critical (slam); Improved Initiative; Iron Will; Spell Focus (abjuration); Weapon Finesse; Weapon Focus (slam)
Skills: Hide -6, Listen +19, Move Silently +20, Search +13, and Spot +19
Advancement: 14-20 HD (Huge); 21-39 HD (Gargantuan)
Climate/Terrain: Any land and underground
Organization: Solitary
Treasure/Possessions: None

Source: Fiend Folio

Dispelling Touch (Sp): If an aoa successfully damages an opponent with its slam attack, the opponent is also affected by dispel magic as if cast by a 15th level wizard.

Reflective Spell Resistance (Sp): An aoa has a special type of spell resistance that causes any targeted spell it successfully resists to bounce off and reflect back at the caster. The caster becomes either the spell's target or the point of origin for the spell's effect, as appropriate. In addition, aoa are immune to gaze attacks, and such an effect is reflected back to its origin.

Outsider Traits: An aoa has darkvision (60-foot range). It cannot be raised or resurrected (though a wish or miracle spell can restore life).

Resistances (Ex): An aoa has fire, cold, electricity, and sonic resistance 20.

Spell-like Abilities: At will - detect magic. Caster level 15th; save DC 15 + spell level.

Skills: Aoa have a -6 racial bonus on Hide checks.

Extraplanar Subtype

A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.

Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.