Kostchtchie, Prince of Wrath (CR 21)

Huge Outsider (Chaotic, Cold, Evil, Extraplanar, and Tanar'ri)
Alignment: Chaotic evil
Initiative: +1(Dex); Senses: darkvision 60 ft., true seeing, Listen +31, and Spot +31
Languages: Abyssal, Common, Giant; telepathy 300 ft.

AC: 41 (-2 size, +1 Dex, +24 natural, +8 armor and/or shield), touch 9, flat-footed 40
Hit Dice: 23d8+322 (425 hp); DR: 20/cold iron and good
Fort +27, Ref +14, Will +18
Speed: 40 ft. (30 ft. in hide armor)
Space: 15 ft.; Reach 15 ft.
Base Attack +23; Grapple +46
Attack: Melee*: +7 icy burst cold iron maul +32/+27/+22/+17 (*Attacks include the Power Attack feat)
Damage: *+7 icy burst cold iron maul 3d8+35/19-20/x3 plus 1d6 cold [plus 2d10 cold on a critical hit])
Special Attacks/Actions: rage, rock throwing, summon tanarri
Attack Options: Awesome Blow, Cleave, Great Cleave, Improved Bull Rush, Power Attack, stunning blow
Abilities: Str 40, Dex 12, Con 38, Int 18, Wis 20, Cha 23
Special Qualities: rock catching, tanarri traits; Immunities: cold, critical hits, electricity, poison; Resist acid 10, fire 10; SR 32; Weakness: vulnerable to fire
Feats: Awesome Blow, Cleave, Dark Speech, Improved Critical (maul), Improved Bull Rush, Power Attack, Track, Weapon Focus (maul)
Skills: Climb +39, Concentration +40, Handle Animal +32, Intimidate +32, Jump +39, Knowledge (the planes) +30, Listen +31, Ride +29, Search +30, Spot +31, Survival +31 (+33 when following tracks), and Swim +37
Advancement: By character class
Climate/Terrain: The Abyss (The Iron Wastes)
Organization: Troupe (two Huge 18 HD leucrottas or two Huge 18 HD winter wolves) or squad (2-4 frost giants and one Huge ancient 30 HD white dragon that serves as his steed)
Treasure/Possessions: +5 heavy fortification hide armor, +7 icy burst cold iron maul

Source: Fiendish Codex I

Rage (Ex): Once per day, Kostchtchie can enter a state of frenzy identical to that of a barbarian's greater rage ability. In this state, Kostchtchie's Strength and Constitution increase by 6 and his morale bonus on Will saves increases by 3. His Armor Class gains a -2 penalty. Kostchtchie remains in his rage for 2 minutes and is not fatigued when he leaves his rage.

While he is raging, Kostchtchie's statistics change as follows: AC 39, touch 7, flat-footed 38 hp 494. Fort +30, Will +21. Melee +7 icy burst cold iron maul +35/+30/+25/+20 (3d8+40/19-20/x3 plus 1d6 cold [plus 2d10 cold on a critical hit]); Ranged rock +22 (2d8+18) Grp +49; Abilities: Str 46, Con 44; Skills: Climb +42, Concentration +43, Jump +42, Swim +40

Rock Catching (Ex): Kostchtchie can catch Small, Medium, or Large rocks (or projectiles of similar shape). Once per round, if he would normally be hit by a rock, Kostchtchie can make a Reflex save to catch it as a free action. The DC is 15 for a Small rock, 20 for a Medium one, and 25 for a Large one. (If the projectile provides a magical bonus on attack rolls, the DC increases by that amount).

He must be ready and aware of the attack in order to make a rock catching attempt.

Rock Throwing (Ex): Kostchtchie can hurl rocks of 60 to 80 pounds (Medium objects) up to five range increments of 140 feet.

Stunning Blow (Su): Kostchtchie's attacks are particularly powerful. Each time he critically hits an opponent, that opponent is automatically stunned for 1 round unless he makes a DC 36 Fortitude save (DC 39 when Kostchtchie is raging). The save DC is Strength-based.

Summon Tanar'ri (Sp): Once per day, Kostchtchie can automatically summon 2d4 babaus or 1 goristro. This ability is the equivalent of a 9th-level spell (CL 20th).

Spell-Like Abilities (CL 20th): At will - astral projection, ice storm, desecrate, detect good, detect law, greater dispel magic, greater teleport, telekinesis (DC 21), unhallow, unholy blight (DC 20), wind walk; 3/day - poison (DC 20), symbol of weakness (DC 23) 1/day - harm (DC 22)

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).

Cold Subtype

A creature with the cold subtype has immunity to cold. It has vulnerability to fire, which means it takes half again as much (+50%) damage as normal from fire, regardless of whether a saving throw is allowed, or if the save is a success or failure.

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).