Mineral Warrior (Stony Devil)* (CR 12)

Medium Outsider (Baatezu, Earth, Evil, Extraplanar, and Lawful)
Alignment: Always lawful evil
Initiative: +6 (+2 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., see in darkness, Listen +18, and Spot +18
Languages: Telepathy 100 ft.

AC: 32 (+6 Dex, +16 natural), touch 16; flat-footed 26
Hit Dice: 12d8+96 (150 hp); DR: 10/good and 8/adamantine
Fort +16, Ref +14, Will +11
Speed: 30 ft., burrow 15 ft.
Space: 5 ft./5 ft.
Base Attack +12; Grapple +23
Attack: Claw +19 melee (2d8+7 plus fear)
Full Attack: 2 claws +19 melee (2d8+7 plus fear)
Special Attacks/Actions: Earth strike, fear, impale 3d8+10, improved grab, spell-like abilities, summon baatezu
Abilities: Str 25, Dex 23, Con 27, Int 10, Wis 12, Cha 16
Special Qualities: Barbed defense, immunity to fire and poison, resistance to acid 10 and cold 10, SR 23
Feats: Alertness; Cleave; Improved Grapple; Iron Will; Power Attack
Skills: Concentration +23, Diplomacy +5, Hide +21, Intimidate +18, Knowledge (any one) +15, Listen +18, Move Silently +21, Search +15, Sense Motive +16, Spot +18, and Survival +1 (+3 following tracks)
Advancement: 13-15 HD (Medium); 16-21 HD (Large)
Climate/Terrain: Nine Hells of Baator
Organization: Solitary, team (2-4), or squad (6-10)
Treasure/Possessions: Standard

Source: Underdark

Earth Strike (Ex): Once per day, a stony devil can make an exceptionally vicious attack against any foe that stands on stone or earth. When using this ability, the stony devil adds +8 to its attack roll and deals 12 extra points of damage.

Fear (Su): A creature hit by a stony devil must succeed on a DC 19 Will save or be affected as though by a fear spell. Whether or not the save is successful, that creature cannot be affected again by that stony devil's fear ability for 24 hours. Caster level 9th. The save DC is Charisma-based.

Impale (Ex): A stony devil deals 3d8+10 points of piercing damage to a grabbed opponent with a successful grapple check.

Improved Grab (Ex): To use this ability, a stony devil must hit with a claw attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and can impale the opponent on its barbed body.

Spell-Like Abilities: At will - greater teleport (self plus 50 pounds of objects only; caster level 12th), scorching ray (caster level 7th). 1/day - order's wrath, unholy blight (DC 17, caster level 7th).

Summon Baatezu (Sp): Once per day, a stony devil can attempt to summon 1d6 bearded devils or a barbed devil with a 35% chance of success. This ability is the equivalent of a 4th-level spell.

Barbed Defense (Su): Any creature striking a stony devil with handheld weapons takes 1d8+9 points of piercing and slashing damage from the barbs that entwine over the monster's body. Weapons with exceptional reach, such as longspears, do not endanger their wielders in this way.

See in Darkness (Su): A stony devil can see perfectly in darkness of any kind, even that created by deeper darkness spells.

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).

Earth Subtype

This subtype usually is used for elementals and outsiders with a connection to the Elemental Plane of Earth. Earth creatures usually have burrow speeds, and most earth creatures can burrow through solid rock.

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).