No Oni, Ugulu (CR 12)

Large Outsider (Evil and Shadowlands)
Alignment: Always chaotic evil
Initiative: -1 (Dex); Senses: Listen +14 and Spot +14
Languages: Telepathy 100 ft.

AC: 24 (-1 size, -1 Dex, +16 natural), touch 8, flat-footed 24
Hit Dice: 9d8+54 (94 hp); DR: 10/jade
Fort +12, Ref +5, Will +8
Speed: 40 ft.
Space: 10 ft./10 ft.
Base Attack +9; Grapple +9
Attack: 2 claws +16 melee
Full Attack: 2 claws +16 melee
Damage: Claw 2d4+8
Special Attacks/Actions: Spell-like abilities, fear aura
Abilities: Str 26, Dex 9, Con 22, Int 11, Wis 14, Cha 11 (Ego: 7)
Special Qualities: spell immunity, oni qualities, regeneration 3
Feats: Cleave; Great Cleave; Improved Bull Rush; Power Attack
Skills: Bluff +12, Diplomacy +4, Intimidate +14, Jump +20, Knowledge (Shadowlands) +12, Listen +14, Search +12, Sense Motive +14, and Spot +14
Advancement: 10-20 HD (Large); 21-30 HD (Huge)
Climate/Terrain: Shadowlands
Organization: Solitary
Treasure/Possessions: Standard

Source: Oriental Adventures

Spell-Like Abilities: At will - cloud of Taint, deeper darkness, desecrate, produce flame, protection from arrows, shatter. These abilities are as the spells cast by a 9th-level maho-tsukai (save DC 17 + spell level).

Fear Aura (Su): Oni are shrouded in a constant aura of terror and evil. Creatures within a 30-foot radius must succeed at a Will save (DC 14) or become shaken. Shaken creatures suffer a -2 morale penalty on attack rolls, weapon damage rolls, and saving throws.

Spell Immunity (Su): Each ugulu no oni is immune to a single spell, effectively giving it unbeatable spell resistance regarding that spell. This immunity protects the oni from the spell, spell-like effects of magic items that duplicate that spell, and innate spell-like abilities of creatures. Roll 1d10 to determine the spell immunity of a given oni:

1bestow curse
2bo of water
3finger of death
4hold monster
5jade strike
6katana of fire
7slay living
8tetsubo of earth
9tomb of jade
10yari of air

Regeneration (Ex): Oni take normal damage from jade or Kuni crystal weapons, and from honorable or blessed weapons of at least +2 enhancement.

Immunities (Ex): Oni are immune to poison.

Resistances (Ex): Oni have cold, fire, and acid resistance 10.

Alternate Form (Su): Oni can assume any humanoid form of Small to Large size as a standard action. This ability is similar to the polymorph self spell but allows only humanoid forms. When using this ability, oni gain a +10 circumstance bonus on Disguise checks.

Telepathy (Su): Oni can communicate telepathically with any creature within 100 feet that has a language.

Skills: All oni receive a +10 circumstance bonus on Disguise checks when using their alternate form ability.

Evil Subtype

A subtype usually applied only to outsiders native to the evil-aligned Outer Planes. Evil outsiders are also called fiends. Most creatures that have this subtype also have evil alignments; however, if their alignments change, they still retain the subtype. Any effect that depends on alignment affects a creature with this subtype as if the creature has an evil alignment, no matter what its alignment actually is. The creature also suffers effects according to its actual alignment. A creature with the evil subtype overcomes damage reduction as if its natural weapons and any weapons it wields were evil-aligned (see Damage Reduction).

Shadowlands Subtype

Shadowlands are the source of evil in the campaign setting of Rokugan, the festering pit from which oni crawl, slither, and fly to wreck their foul destruction on humanity. The denizens of the Shadowlands are inhuman monstrosities. Many of them are spirits bound into corporeal form, and most are shapeshifters. Of all the creatures found in the Shadowlands, only the nezumi remain uncorrupted by the foul taint of the place - all others are utterly, irredeemably evil.

Shadowlands creatures share a certain immunities and vulnerabilities. They are immune to harmful effects of the Shadowlands Taint, for they are already fully corrupted by their very nature. Even if they have damage reduction, they are harmed by jade and obsidian weapons, and they cannot regenerate or naturally heal wounds dealt by such weapons. They are also affected by crystal weapons (Chapter 8, Oriental Adventures) (Note: Non-magical weapons made out of crystal, or crystal weapons created by means other than the Craft Crystal Weapon feat, have no special properties against Shadowlands creatures.)

For purposes of detect Taint, spellcasting, and other effects, a Shadowlands creature is considered to have a Taint score equal to half its Charisma score (round down). Undead creatures add +1 to this number, while outsiders add +2.