Half-Fiend/Human* (CR 9)

Medium Outsider (Augmented Humanoid and Native)
Alignment: Always evil (any)
Initiative: +7 (+3 Dex, +4 Improved Initiative); Senses: darkvision 60 ft. and Spot +9


AC: 24 (+3 Dex, +1 natural, +10 +2 breastplate and+1 heavy shield), touch 13, flat-footed 21
Hit Dice: 7d8+14 (49 hp); DR: 5/magic
Fort +7, Ref +5, Will +9
Speed: 30 ft., fly 30 ft. (average) (20 ft. in breastplate, fly 20 ft. (average) in breastplate)
Space: 5 ft./5 ft.
Base Attack +5; Grapple +9
Attack: +1 morningstar +11 melee or claw +9 melee or masterwork light crossbow 9 ranged
Full Attack: +1 morningstar +11 melee and bite +4 melee; 2 claws +9 melee and bite +4 melee; or masterwork light crossbow 9 ranged
Damage: +1 morningstar 1d8+5, bite 1d6+2, claw 1d4+4, masterwork light crossbow 1d8/19-20
Special Attacks/Actions: Smite good, spells, spell-like abilities, rebuke undead 8/day
Abilities: Str 18, Dex 17, Con 14, Int 12, Wis 18, Cha 12
Special Qualities: 7th lvl Cleric of Erythnul, immunity to poison, resistance to acid 10, cold 10, electricity 10, and fire 10, SR 17
Feats: Combat Casting; Extra Turning; Flyby Attack; Improved Initiative; Weapon Focus (morningstar)
Skills: Concentration +12, Diplomacy +6, Knowledge (arcana) +6, Knowledge (religion) +6, Spellcraft +3, Spot +9, and heal +9
Advancement: By character class
Climate/Terrain: Temperate plains
Organization: Solitary
Treasure/Possessions: Double Standard

Source: Monster Manual

Half-fiend spellcasters such as the one described here are usually found as the leaders of dark cults or evil temples.

Combat

Half-fiends attack with aggressiveness and battle lust, using their ability to fly to best advantage by casting spells from the air. They enjoy torturing any enemies unfortunate enough to fall into their hands.

Smite Good (Su): Once per day this half-fiend can make a normal melee attack to deal 7 points of extra damage against a good foe.

Spell-Like Abilities: 3/day - darkness, poison (DC 15); 1/day - desecrate, unholy blight (DC 15). Caster level 7th. The save DCs are Charisma-based.

Typical Cleric Spells Prepared (6/6/5/4/3; save DC 14 + spell level): 0 cure minor wounds, detect magic, guidance, light, read magic, resistance; 1st - command, cure light wounds, divine favor, doom, protection from good*, shield of faith; 2nd - bear's endurance, bull's strength, hold person, sound burst, spiritual weapon*; 3rd - bestow curse, cure serious wounds, dispel magic, magic vestment*; 4th - cure critical wounds, summon monster IV, unholy blight*.

*Domain spell. Deity: Erythnul. Domains: Evil (cast evil spells at +1 caster level) and War (Weapon Focus bonus feat).

Possessions: +2 breastplate, +1 large steel shield, +1 morningstar, periapt of Wisdom +2, potion of haste. (Different half-fiends may have different possessions.)

Augmented Subtype

A creature receives this subtype whenever something happens to change its original type. Some creatures (those with an inherited template) are born with this subtype; others acquire it when they take on an acquired template. The augmented subtype is always paired with the creature's original type. For example, a wizard's raven familiar is a magical beast (augmented animal). A creature with the augmented subtype usually has the traits of its current type, but the features of its original type. For example, a wizard's raven familiar has an animal's features and the traits of a magical beast.

Native Subtype

A subtype applied only to outsiders. These creatures have mortal ancestors or a strong connection to the Material Plane and can be raised, reincarnated, or resurrected just as other living creatures can be. Creatures with this subtype are native to the Material Plane (hence the subtype's name).

Unlike true outsiders, native outsiders need to eat and sleep.