ne large fiend fire giant humanoid oni 

Perception +26; greater darkvision

Languages Common, Jotun

Skills Acrobatics +23, Arcana +23, Athletics +27, Crafting +25, Deception +27, Intimidation +27, Nature +25

Str +8 Dex +6 Con +6 Int +4 Wis +6 Cha +8

Items +1 resilient breastplate, +2 striking katana

AC  36; Fort +28, Ref +26, Will +24

HP 250, regeneration 15 (deactivated by acid or cold); Immunities fire

Attack of Opportunity [R]

Speed 40 feet, fly 40 feet

Melee [>] katana +30 (deadly 1d8, magical, reach 10 feet, two-hand d10, versatile p), Damage 2d6+16 slashing plus 2d6 fire

Melee [>] fist +28 (agile, evil, magical, reach 10 feet), Damage 2d6+16 bludgeoning plus 2d6 fire and 2d6 persistent fire

Ranged [>] fire missile +26 (evil, fire, magical, range increment 60 feet), Damage 2d10+16 fire plus 2d6 persistent fire

Primal Innate Spells DC 34; 7th fireball, fiery body, flame strike, wall of fire; 6th fireball (×3); 4th charm (×3), darkness, gaseous form; 2nd invisibility (at will, self only)

Change Shape [>] (concentrate, polymorph, primal, transmutation) The fire yai takes on the appearance of a fire giant. This doesn't change their Speed or Strike attack and damage.

Impaling Push [>>] The fire yai attempts a katana Strike. If it hits, the fire yai attempts an Athletics check against the target creature's Fortitude DC. Critical Success The fire yai Strides or Flies up to half its Speed in any direction. The struck creature takes 4d6 persistent bleed damage and is pushed along with the yai an equal distance. The creature is grabbed until the yai's next turn or until the yai makes a katana Strike.Success As critical success, but the creature takes 2d6 persistent bleed damage.Failure The struck creature is pushed back 5 feet.Critical Failure The struck creature is unaffected.

Smoke Form [>>] (concentrate, primal, transmutation) The fire yai transforms into a cloud of smoke and then Flies up to its fly speed. This movement does not trigger reactions, and the fire yai can move through spaces occupied by other creatures. The fire yai returns to its physical form after this move, and must end the movement in a space in which it can fit. All creatures in spaces through which the fire yai moves with Smoke Form must succeed at a DC 34 Fortitude save or become sickened 3. The fire yai cannot use Smoke Form for 1d4 rounds.

Bestiary 2, page 190.