Erupting from the sand before you is a large, vaguely gnoll-like creature that seems to be all fangs, claws, and broad brown quills.

Irrinja (CR 5; XP 1,600)
CE Large monstrous humanoid (shapechanger)
Init +5; Senses darkvision 60 ft., scent; Perception +12
AC 19, touch 14, flat-footed 14
(+5 Dex, +5 natural, -1 size)
hp 51 (6d10+18)
Fort +5, Ref +10, Will +8
Defensive Abilities desert master, sand rebirth
Speed 30 ft., 40 ft. on all fours
Melee bite +9 (1d8+4 plus grab), 2 claws +9 (1d6+4)
Space 10 ft.; Reach 10 ft.
Special Attacks fast swallow (1d6+3 acid, AC 12, hp 5), pounce
Str 19, Dex 20, Con 17, Int 14, Wis 16, Cha 10
Base Atk +6; CMB +11 (+15 grapple); CMD 26 (30 vs. trip when on all fours)
Feats Combat Reflexes, Intimidating Prowess, Stand Still
Skills Climb +13, Intimidate +13, Knowledge (geography) +8, Perception +12, Stealth +10, Survival +12
Languages Common, Old Porphyran, Terran
SQ change shape (alter self)
Environment desert
Organization solitary, pair, or pack (4-10)
Treasure standard
Special Abilities
Desert Master (Ex) The irrinja is never affected by adverse desert conditions or weather. It never treats desert terrain as difficult terrain.
Quadruped Movement (Ex) An irrinja may, as a free action, drop anything in its hands and revert to a four-legged mode of transportation, increasing its speed to 40 feet and gaining a +4 bonus to CMD to resist trip attacks. Its reach drops to 5 ft. in this form.
Sand Rebirth (Su) The irrinja gains sustenance from the desert sands, even when slain. Any dead irrinja that is completely covered by desert sand is subjected to an effect identical to true resurrection. If the irrinja is merely wounded it can cover itself completely with sand, as a full-round action, to gain fast healing 3.

Fearsome predators of the desert, irrinjas claim large territories in sandy wastes, and woe betide the traveler that thinks himself too clever for the “desert demons”. Their innate shapechanging power is limited to beings that they have seen and encountered, though their memories are very long, and rather inventive. Far more than mere brutes, irrinjas harbor a sharp intelligence that is frequently underestimated – mostly because of their resemblance to gnolls. While the relationship between the two races is not clear, gnolls and irrinjas will work together, the larger predator using the weapon-wielding hyena-men to drive prey into its clutches; they will also often assume gnoll form and appear to fight alongside them, until opponents discover a stranger truth. Irrinjas consume all flesh and bone, but disdain artifacts of any kind.

Within their own kind, irrinjas are fractious and constantly compete for dominance within the pack, which often results in a smaller pack. The winner of a serious challenge will completely consume the loser, preventing their peculiar form of regeneration. A clever leader will prepare many sorts of ambushes, such as leaping from a rock face onto a caravan to create mayhem, retreating to quickly heal up, and then returning for a frontal assault or infiltration.

On Porphyra
Irrinjas are found throughout the desert lands of Porphyra, though almost always near rock formations and mountain ranges such as the Mountains of Wrath and the Crumbs of Aish. Though assumed to be a mutated form of gnoll, the grim truth is that they are offshoots of the advanced race of anpur, created by fell magic and infusions of demonic ichor.