Amnizu (CR 7)

Medium Outsider (Baatezu, Evil, Extraplanar, and Lawful)
Alignment: Always lawful evil
Initiative: +4(+0 Dex, +4 Improved Initiative); Senses: see in darkness and Spot +17
Languages: Celestial, Draconic, Infernal; telepathy 100ft.

AC: 21 (+0 Dex, +11 natural), touch 10, flat-footed 21
Hit Dice: 9d8+9 (49 hp); DR: 10/good
Fort +7, Ref +6, Will +8
Speed: 30 ft. and Fly 60 ft. (average)
Space: 5 ft./5 ft.
Base Attack +9; Grapple +10
Attack: Melee: stupifying touch +10
Damage: Stupifying touch 1d4 plus Int damage)
Special Attacks/Actions: summon baatezu
Abilities: Str 12, Dex 11, Con 13, Int 15, Wis 11, Cha 16
Special Abilities: stupefying touch, spell-like abilities, summon baatezu
Special Qualities: regeneration 4; Immunites:fire, poison; secure intelligence; Resist acid 10, cold 10; SR 18
Feats: Ability Focus (stupefying touch), Combat Casting, Improved Initiative, Quicken Spell-Like Ability (fireball),
Skills: Balance +6, Concentration +13, Diplomacy +9, Hide +12, Jump +7, Knowledge (the planes) +14, Search +14, Sense Motive +12, Spellcraft +14, Spot +17, Survival +0 (+2 on other planes or follow tracks), Swim +13, and Tumble +12
Advancement: 10-18 HD (Medium); 19-27 HD (Large)
Climate/Terrain: Nine Hells of Baator
Organization: Individual, Conspiracy (2-4 ), Troupe (hunting party)
Treasure/Possessions: Standard (mostly potions and wondrous items)

Source: Fiendish Codex II
Monster Manual II

Regeneration (Ex): Acid, good-aligned weapons, and spells or effects with the good descriptor deal normal damage to an amnizu.

Secure Intelligence (Ex): Immune to any effect that would damage, drain, or otherwise reduce its Intelligence score.

Stupefying Touch (Su): In addition to the damage, creatures struck by stupefying touch must succeed on a DC 19 Will save or take 2d4 points of Intelligence damage. The save DC is Charisma-based.

Spell-Like Abilities (CL 14th): 3/day - quickened fireball (DC 16)

Updated to Fiendish Codex II

Baatezu Subtype

Many devils belong to the race of evil outsiders known as the baatezu.

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

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.

Lawful Subtype

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