Sibriex (CR 15)

Large Outsider (Chaotic, Evil, Extraplanar, and Obyrith)
Alignment: Always chaotic evil
Initiative: -4 (Dex); Senses: darkvision 60 ft., true seeing, Listen +25, and Spot +25
Languages: Abyssal; telepathy 100 ft.

AC: 25 (-1 size, -4 Dex, +20 natural), touch 5, flat-footed 25
Hit Dice: 15d8 (217 hp); DR: 15/cold iron and lawful
Fort +19, Ref +5, Will +16
Speed: Fly 20 ft. (good)
Space: 10 ft./5 ft. (15 ft. with chains)
Base Attack +15; Grapple +25
Attack: 4 chains +20 melee and bite +15 melee
Damage: 4 chains 2d6+6, bite 1d8+3
Special Attacks/Actions: animate chains, instant graft, squirt bile, spell-like abilities
Attack Options: Combat Expertise, Improved Trip
Abilities: Str 22, Dex 3, Con 30, Int 25, Wis 24, Cha 25
Special Qualities: Fast healing 10; Immune acid, mind-affecting spells and effects, nausea, poison, Resist cold 10, electricity 10, fire 10; SR 26, immobility, form of madness, flight, obyrith traits
Feats: Combat Expertise; Dark Speech; Graft Flesh (fiendish grafts); Greater Spell Focus (enchantment); Improved Trip; Spell Focus (enchantment)
Skills: Bluff +25, Concentration +28, Decipher Script +25, Diplomacy +29, Gather Information +25, Heal +25, Intimidate +27, Knowledge (arcana) +25, Knowledge (the planes) +25, Listen +25, Search +25, Sense Motive +25, Spellcraft +27, Spot +25, and Use Magic Device +25 (+29 scrolls)
Advancement: 16-29 HD (Large); 30-45 HD (Huge)
Climate/Terrain: Any land and underground
Organization: See text
Treasure/Possessions: Double standard (magic items)

Source: Fiendish Codex I

Chaotic Subtype

A subtype usually applied only to outsiders native to the chaotic-aligned Outer Planes. Most creatures that have this subtype also have chaotic 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 a chaotic alignment, no matter what its alignment actually is. The creature also suffers effects according to its actual alignment. A creature with the chaotic subtype overcomes damage reduction as if its natural weapons and any weapons it wields were chaotic-aligned (see Damage Reduction).

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).

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.

Obyrith Subtype

The strange and horrific Obyriths are primeval demons from eons past. They wrought chaos and evil upon the multiverse before the advent of intelligent life on the Material Plane. Their forms are hideous to behold, rarely if ever incorporating elements possessed by mortal creatures. Obyriths dwell only in the most remote corners of the Abyss. Their kind has been in decline since the rise of the tanar'ri in the Abyss, although a few tenacious examples continue to make their presence known on key layers.

Traits: An obyrith has the following traits (unless otherwise noted in a creature's entry).