Graz'zt, The Dark Prince (CR 22)

Large Outsider (Chaotic, Evil, Extraplanar, and Tanar'ri)
Alignment: Chaotic evil
Initiative: +13(+9 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., true seeing, Listen +35, and Spot +35
Languages: Common, Draconic, Giant, Infernal; telepathy 300 ft.

AC: 60 (-1 size, +9 Dex, +22 natural, +13 armor, +7 shield), touch 18, flat-footed 51; displacement 50% miss chance
Hit Dice: 27d8+324 (445 hp); DR: 20/cold iron and good
Fort +27, Ref +24, Will +20
Speed: 40 ft. (30 ft. in full plate)
Space: 10 ft.; Reach 10 ft.
Base Attack +27; Grapple +39
Attack: Melee*: +5 acidic burst bastard sword +34/+29/+24/+19 or Melee: +5 acidic burst bastard sword +41/+36/+31/+26
Damage: *+5 acidic burst bastard sword (2d8+32/17-20 plus 1d6 acid [plus 1d10 acid on a critical hit]) (*Attacks include Power Attack feat)
Special Attacks/Actions: fear, summon tanarri
Attack Options: Cleave, Combat Expertise, Power Attack
Abilities: Str 27, Dex 28, Con 35, Int 33, Wis 20, Cha 38
Special Qualities: tanarri traits, fast healing 10; Immunities: electricity, poison; Resist acid 10, cold 10, fire 10; SR 33
Feats: Cleave, Combat Expertise, Dark Speech, Dodge, Empower Spell-Like Ability (unholy blight), Exotic Weapon Proficiency (bastard sword), Improved Critical (bastard sword), Improved Initiative, Power Attack, Weapon Focus (bastard sword),
Skills: Balance +2, Bluff +44, Concentration +42, Diplomacy +48, Disguise +44 (+46 acting in character), Forgery +41, Gather Information +44, Hide +27, Intimidate +46, Jump +8, Knowledge (arcana) +41, Knowledge (history) +41, Knowledge (religion) +41, Knowledge (the planes) +41, Listen +35, Move Silently +30, Search +41, Sense Motive +35, Spellcraft +43, Spot +35, and Tumble +30
Advancement: -
Climate/Terrain: The Abyss
Organization: Grazzt plus 6 lamias, succubi, or mariliths
Treasure/Possessions: +5 mithral glamered full plate, +5 heavy steel shield, +5 acidic burst bastard sword, major cloak of displacement

Source: Book of Vile Darkness
Fiendish Codex I

Fear (Su): As a free action, Graz'zt can inspire fear (as the spell of the same name) by sneer and word once per round in any target creature within 60 feet. This effect can be resisted with a DC 37 Will save. This is a mind-affecting fear ability. The save DC is Charisma-based.

Summon Tanar'ri (Sp): Once per day, Graz'zt can automatically summon 1d2+l glabrezu or 1 balor. This ability functions as a 9th-level spell (CL 20th).

Spell-Like Abilities (CL 20th): At will - astral projection, charm monster (DC 28), desecrate, detect good, detect law, greater dispel magic, greater teleport, telekinesis (DC 29), unhallow, unholy blight (DC 28) 3/day - dominate person (DC 28), empowered unholy blight (DC 28), symbol of persuasion (DC 30) 1/day - trap the soul (DC 33)

Updated to 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.

Tanarri Subtype

Most demons encountered outside of the Abyss are tanar'ri. The most populous of the demon subtypes, the tanar'ri form the largest and most diverse group of demons. They are the unchallenged masters of the Abyss at this time. The first tanar'ri were forged from the souls of the first humanoids drawn to the Abyss. Most tanar'ri incorporate humanoid features into their forms as a result of their close ties to the mortal realm.

Traits: A tanar'ri possesses the following traits (unless otherwise noted in a creature's entry).