This is the main opponent at the moment, a former ruler of a layer of Hell. He’s the bastard son of Halgrin (god of suffering and torture) and a pit fiend. He’s killed a major NPC ally of the party and a PC, and he’s bought out a major ally of the party, the rock dragon Vorgixat. At the moment he’s keeping a low profile, sending a paleolich assassin after the remaining PCs. Do you have any idea what CR he might be?
---------- Not for visual consumption by Charles' players ----------
Kaziglu, Infernal Child of Halgrin
Assassin1/Rogue13
Large Outsider (Evil, Extraplanar)
Hit Dice: 14d6+40d8+540 (944 hp)
Initiative: +15
Speed: 80 ft, fly 240 ft (perfect)
Armor Class: 41 [52 vs. ranged] (-1 size, +8 Dex, +24 natural), touch 17, flat-footed 41
Base Attack/Grapple: +40 (+7 EA)/+67
Full Attack: 2 claws +65 melee (4d6+16 plus 1 vile), bite +60 melee (6d6+8 plus spell suck and 1 vile), tail slam +60 melee (4d8+8 plus 1 vile)
Space/Reach: 10 ft/10 ft (15 ft with claws)
Special Attacks: Improved grab, spell suck, learned spell immunity, spell-like abilities, spells, summon fiend, sneak attack +8d6, death attack, crippling strike
Special Qualities: Abomination traits, fast healing 15, regeneration 15, SR 38, DR 15/good and epic, senses, electricity resistance 10, fire resistance 20, cold resistance 20, poison use, improved evasion, trapfinding, trap sense +4, improved uncanny dodge, deflection
Saves: Fort +39, Ref +37, Will +37
Abilities: Str 42, Dex 26, Con 30, Int 22, Wis 26, Cha 32 (20-point buy)
Skills: Balance +12 (0), Bluff +72 (57), Concentration +54 (43), Climb +16 (0) [+20 climbing rope], Diplomacy +25 (0), Disguise +15 (4), Escape Artist +43 (35) [+47 escaping rope bonds], Gather Information +15 (0), Hide +47 (43), Intimidate +88 (57), Jump +21 (0), Knowledge (arcana) +49 (43), Knowledge (nobility and royalty) +28 (22), Knowledge (religion) +27 (21), Knowledge (the planes) +49 (43), Listen +67 (57), Move Silently +51 (43), Perform (any) +15 (0), Profession (torturer) +71 (57), Search +49 (43), Sense Motive +51 (43), Spellcraft +53 (43), Spot +67 (57), Tumble +51 (43), Use Rope +43 (35) [+47 binding with rope]
Feats: Alertness, Cleave, Combat Expertise, Combat Reflexes, Great Cleave, Improved Initiative, Improved Sunder, Multiattack, Power Attack, Vile Natural Attack, Weapon Focus (claw)
Epic Feats: Blinding Speed (2), Energy Resistance (electricity), Epic Reputation, Epic Skill Focus (Intimidate), Epic Weapon Focus (claw), Lingering Damage, Spellcasting Harrier, Superior Initiative
Environment: Any
Organization: Solitary or hell brigade (infernal and 4 balors or pit fiends)
Challenge Rating: ?
Treasure: Nonstandard (layer of Hell)
Alignment: Always neutral evil
Advancement: 41-50 HD (Large); 51-56 HD (Huge); 57-72 HD (Gargantuan)
Level Adjustment: —
COMBAT
Abomination Traits:
—Immunity to polymorphing, petrifaction, or any form-altering attack. They are not subject to energy drain, ability drain, or ability damage. They are immune to mind-affecting effects (charms, compulsions, phantasms, patterns, and morale effects).
—Resistance to fire 20 and cold 20.
—True seeing and nondetection are always active
—Blindsight 500 feet
—Maximum hit points per Hit Die
—Telepathy 1000 feet with all creatures that use a language
Spell-Like Abilities: At will—Quickened abyssal might M, demand, greater dispel magic, polymorph self, greater scrying, telekinesis, greater teleport, wall of fire; 3/day—bestow greater curse, Quickened bone blast M, death by thorns (Corruption: 1d3 Wis); 1/day—eternity of torture. Caster level 26th; save DC 21 + spell level.
Summon Fiend (Sp): 5/day, duration 1 hour: 4 balors or 4 pit fiends.
Regeneration (Ex): Normal damage from good weapons.
Learned Spell Immunity (Su): Once a particular caster affects the infernal with a spell, he can’t affect the infernal with that spell ever again.
Spell Suck (Su): On a bite, target loses highest level spell or slot. If there are no spells or slots, instead take 2 Int damage.
Improved Grab (Ex): To use this ability, the infernal must hit a Large or smaller opponent with its bite 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 automatically deals bite damage and uses spell suck.
Senses (Su): Low-light vision and darkvision (240 ft); keen senses; detect good, detect chaos, detect law.
Ranged Deflection (Su): Kaziglu adds his Cha modifier to AC as a deflection bonus against ranged attacks.
Assassin Spells Known (–/2): 1—jump, true strike.
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I am really looking forward to seeing the final product! 
