
Kaushal Avan Spellfire |

Hey guys, I'm trying to design a CR 21 monster to throw up against my level 17 party. He's to play the role of the "big bad" and be appropriately epic. Setting aside your reservations about "god-slaying," is this an appropriate challenge rating? Should I remove certain abilities (the divine rank perhaps)?
Any suggestions of what I should model my CR 21 boss off of?
Just to note: the boss's DR will NOT be a problem as they will have an enchantment designed to overcome his DR.
Some background: Bel is the god of violence and war in my campaign setting. He has four arms and his weapon is the flail.
Also, to my player who reads these boards: NO PEEKING!
Bel the Slaughterer CR 21
Divine Ranks 1
CE large outsider (chaotic, extraplanar, evil)
Init +7; Senses darkvision 1 mile, low-light vision, remote sensing, true seeing; Spot +38, Listen +38
Languages dark speech, all
Aura divine aura (DC 19, 10 ft)
DEFENSE
AC 39, touch 14, flat-footed 31
(-1 size, +7 dex, +14 natural, +8 deflection)
hp 360 (20 HD); DR 15/epic and good
Resist fire 6; SR 33
Immune ability damage, ability drain, acid, cold, electric, energy drain, mind-affecting attacks, transmutation
Fort +23, Ref +20, Will +20
OFFENSE
Speed 60 ft. (12 squares)
Melee +3 unholy adamantine flail +35 (2d6+15 plus 2d6 evil against good)
Melee four +3 unholy adamantine flail +33/+28/+23/+18 (2d6+15 plus 2d6 evil against good), +33/+33/+33/+28/+28/+28/+23/+18 (2d6+10 plus 2d6 evil against good)
Melee two slams +31 (1d10+12)
Base Atk +20; Grp +36
Atk Options great cleave, power attack, smite 1/day
Special Actions murderous momentum, summon servants, touch of Bel
Spell-like Abilities (CL 20th):
at will- animate dead, blade barrier (DC 24), blasphemy, cause fear (DC 19), contagion (DC 21), create greater undead, create undead, death knell (DC 20), death ward, desecrate, disintegrate (DC25), dispel good (DC 23), divine power, earthquake (DC 26), flame strike (DC 23), harm (DC 24), implosion (DC 27), inflict critical wounds (DC 22), inflict light wounds (DC 19), magic circle against good, magic vestment, magic weapon, mass inflict light wounds (DC 23), power word blind, power word kill, power word stun, protection from good, shatter (DC 20), slay living (DC 23), spiritual weapon, summon monster IX (evil monsters only), unholy aura (DC 26), unholy blight (DC 22), wail of the banshee (DC 27)
STATISTICS
Abilities Str 35, Dex 25, Con 31, Int 24, Wis 24, Cha 26
SQ alternate form, battlemaster, damage reduction 15/epic and good, immortality, remote communication, remote sensing
Feats Cleave, Dark Speech, Improved Multiattack, Greater Cleave, Power Attack, Two-Weapon Fighting, Weapon Focus (flail)
Salient Divine Abilities control creatures (DC 19), frightful presence (DC 24)
Skills Bluff +31, Concentration +33, Diplomacy +35, Disguise +8 (+10 acting), Hide +26, Intimidate +33, Knowledge (history) +30, Knowledge (religion) +30, Listen +38, Move Silently +30, Search +30, Sense Motive +30, Spellcraft +30 (+32 scrolls), Spot +38, Survival +7, Use Magic Device +31 (+33 scrolls)
Possessions four +3 unholy adamantine flails.
SPECIAL ABILITES
Portfolio battle, death, massacre, rage, war
Alternate Form (Su) As a standard action, Bel may assume the form of a male or female human, half-orc, or orc. This functions similarly to the polymorph spell, except that Bel does not heal when he changes shape. Bel gains the physical ability scores of the new form, but retains his mental scores and all of his abilities. Bel does not gain the exceptional, supernatural, or spell-like abilities of his new form, but he does receive any racial bonuses and traits that would be acquired.
Battlemaster (Ex) Bel is considered proficient with all simple, martial, and exotic weapons, as well as all armors and shields, including tower shield.
Control Creatures (Su) Once per day, Bel may attempt to seize control of one giant, humanoid, or monstrous humanoid's body, as if by dominate monster, except it is not a mind-affecting ability (Bel seizes direct control over the creature's body). The creature to be affected must be within Bel's line of sight to be targeted. Once control is established, distance is not a factor and Bel remains in control remotely, even across planes and through wards or barriers (except by divine shields or divine wardings cast by dieties with 2 or more divine ranks). The subject is allowed a DC 19 will save to resist the effect and is allowed a new save if Bel commands the subject to do something against its nature. The saving throw is charisma-based.
Divine Aura (Ex) The mere presence of Bel can deeply affect mortals, granting them resolve in the name of carnage. All of Bel's allies receive a +4 morale bonus on attack rolls, saving throws, and checks, while his foes receive a -4 morale penalty on attack rolls, saves, and checks. A DC 19 Will save negates the effect. Any creature that makes the save is immune to the aura for one day. Bel can choose and set the size of the divine aura as a free action, to a maximum of 10 ft. If Bel sets the aura at 0 ft. then it becomes effectively non-functional. This is a mind-affecting effect.
Domain Powers (Su) Bel gains the ability to use the domain powers of the chaos, destruction, and evil domains once per day.
Frightful Presence (Su) Whenever Bel attacks, charges, or roars, foes within a 30 ft. radius burst must make DC 19 Will saves. Foes within the burst, but not Bel's immediate target, become shaken for 3d6 rounds if they fail their saves. Creatures Bel attacks when it activates the ability become panicked for 3d6 rounds if they fail their saves. Foes who make successful saving throws are unaffected by this ability for one day.
Godly Realm Bel possesses a personal residence and fortress known as the Iron Citadel. It is here where he is most powerful and he possesses at least modest control over the environment of the Citadel. Bel may set the temperature of the fortress between -20 F and 120 F and fill the area with any scents and sounds that he sees fit. Sounds can be no louder than what 100 men could make, but he cannot create intelligable speech or harmful sounds. Bel's ability to create scent is similar.
Immortality (Ex) Bel is immortal and cannot die from natural causes. Bel does not age, and he does not need to sleep, eat or breath. Bel may be slain in magical or physical combat. Bel is not subject to death from massive damage.
Murderous Momentum (Su) When Bel drops an enemy and performs a cleave, he receives a +1 circumstantial modifier to damage rolls for each prior enemy he has dropped. For example, if Bel attacks a foe and drops him, he may cleave into the next foe and deal 1 additional damage with his weapon. If that attack drops the foe he cleaves into, he may cleave again at a +2 bonus. If Bel reaches a +10 bonus from ten consecutive cleaves, then he may move up to 60 ft. in any direction and continue the cleave. Moving like this constitutes as a charge and provokes attacks of opportunity. Bel may only charge once this way per round.
Remote Communication (Su) Bel may telepathically contact any one of his worshipers or anyone within one mile of a holy site or likeness of him as a standard action. Only the creature being contacted can hear Bel. The contact may also be issued out of the air, the ground, or a likeness of him (in which case any creature within earshot can hear the command). The communication can penetrate barriers and cross planes. Bel may continue the contact as a free action until he chooses to end it. Bel can carry on a remote communication at one time as he can carry on a remote sensing at one time.
Remote Sensing (Su) As a standard action, Bel can perceive everything within a radius of one mile around any of his worshipers, unholy sites, or other objects or locales sacred to him. This effect can also be centered on anyone who has spoken his name or title for up to 1 hour after the name has been spoken, and at any location relevant to Bel's portfolio sense. Remote sensing is not fooled by spells such as misdirection, nondetection or similar spells. Bel may focus on two remote sensings at once and still focus on what is going on around him.
Summon Servant (Sp) Once per day Bel can automatically summon 4d10 dretches, 3d6 silent ones, 1d10 silent one witches, 1d10 silent one hunters, 1d4 belspawn, 1d4 hezrous, or one nalfeshnee, greater silent one hunter, marilith, or balor. This ability is the equivalent of a 9th-level spell
Touch of Bel (Su) Once per day, Bel may bestow the touch of Bel upon a living, willing creature. Through this touch, Bel channels its rage and lust for blood, stoking the blood of the recipiant and transforming them into something different. The touched creature receives the Bel-touched template, as detailed elsewere.
Only a humanoid, giant, monstrous humanoid, or magical beast may receive the template, provided they do not already possess the evil subtype. Once the transformation begins, it takes 24 hours to complete. For those 24 hours, the creature is wracked with a terrible pain that prevents it from moving as its body undergoes numerous changes.
Before you stands a black-skinned figure with long, shock-white hair braided into numerous dreadlocks and matted with blood. Its hateful yellow eyes seem to seethe with murderous energy and he bears a toothy grin of razor-sharp teeth between which blood oozes. It each of its four hands in grasps a viscious-looking flail.
Bel may automatically perfom any action pertaining to his portfolio as long as the DC is 15 or lower as a free action twice a round.
Bel may craft any magic item relevant to his portfolio with a maximum cost of 4,500 gp. The item's cost and creation time remain unchanged, but Bel is free to undertake any actions he feels while not laboring on the item.
Bel may grant spells to clerics of Bel and blackguards who pray to him. Bel may withhold spells from any particular mortal as a free action; once a spell has been granted, it remains in the mortal's mind until expended.
Any weapon Bel wields, as well as his natural weapons, are treated as chaotic, epic, and evil for the purposes of overcoming damage reduction.
Silent Ones and Belspawn are both creatures of my own making, which I have already playtested. Belspawn are CR 10, Silent Ones are CR 5, Silent One Hunters and Witches are CR 9, while greater silent one hunters are CR 13.
Please pardon any typos or formatting errors, it's pretty tough to catch everything in a document this large.

Maeloke |

That is one hell of a statblock.
Some things I notice:
-I'm pretty sure the concept of divine ranks is a relic from a 3.0 book. I don't know what precisely they do, but they're not Pathfinder-balanced.
-Same observation about his special cleave ability. It looks like it uses the cleave mechanic from 3.5, rather than pathfinder.
-Normally, multiple off-handed weapons don't get iterative attacks. This is especially bad because the only appropriate feat he has is two-weapon fighting. Should probably be replaced with multiweapon fighting.
-He's missing 2 feats. If you're inclined to justify the huge number of flail attacks, I'd make up a couple feats like improved multiweapon fighting and greater multiweapon fighting. They're unbalanced, but he *is* a god. Otherwise, I'd call the crazy # of attacks divine power, and spend the feats on improved critical and quicken spell-like ability.
-You're using the wrong formula for many of his save DCs, notably frightful presence and control creatures. Strictly charisma-based effects should be 10 + 1/2 HD + cha, or 28 for this chap.
Overall:
Honestly, I don't really like Bel as an encounter. His defensive numbers are tops, so the party will probably be beating their heads against a wall trying to even touch him with iterative attacks and abilities that require saves, especially spells. If permitted a full attack in melee range, he throws out stupid amounts of damage - easily enough to take out a PC in one round, power attacking.
Unfortunately, melee is only of marginal utility here, as his mobility and other strategic options are abysmal. He wields 4 flails, but has no interesting combat maneuvers to attempt with all that weaponry. I don't know how your players do things, but a smart party will stay out of his reach, and as far as I can tell, Bel can't get at someone who is levitating, much less any form of flight, etherealness, gaseous form, etc. This will force him to use spell-like abilities, since he has no other ranged attacks. Of these, probably his best option is to spam wail of the banshee, which makes for a very boring fight. He has no ability to dispel magic, so he's forced to battle a party through all of their buffs. If they're bright, they'll cast magic circle vs. evil and death ward straight off, so there go many of his best options.
I respect all the effort that's gone into this guy, but I think he's probably inferior in combat to a balor or pit fiend with the advanced simple template. In short, not a CR 21.
On the other hand, if you add in better mobility (fly 60 at the minimum, and quickened dimension door will let him move+full attack), a more diverse selection of spell-like abilities (greater dispel magic) and some interesting tactical abilities (flails are good for disarm and trip) his other strengths will probably push him to a CR 23-ish encounter. At that point, your only real problem is that he's still slogging along with a single action each round, has no way to regain hit points, and doesn't really have a good "This is going badly, its time to retreat" ability.

Kaushal Avan Spellfire |

That is one hell of a statblock.
Some things I notice:
-I'm pretty sure the concept of divine ranks is a relic from a 3.0 book. I don't know what precisely they do, but they're not Pathfinder-balanced. Formulas are 3.5 derived, not PF. This also explains why he is "missing" two feats.-Same observation about his special cleave ability. It looks like it uses the cleave mechanic from 3.5, rather than pathfinder.
-Normally, multiple off-handed weapons don't get iterative attacks. This is especially bad because the only appropriate feat he has is two-weapon fighting. Should probably be replaced with multiweapon fighting.
-He's missing 2 feats. If you're inclined to justify the huge number of flail attacks, I'd make up a couple feats like improved multiweapon fighting and greater multiweapon fighting. They're unbalanced, but he *is* a god. Otherwise, I'd call the crazy # of attacks divine power, and spend the feats on improved critical and quicken spell-like ability.
-You're using the wrong formula for many of his save DCs, notably frightful presence and control creatures. Strictly charisma-based effects should be 10 + 1/2 HD + cha, or 28 for this chap.
Overall:
Honestly, I don't really like Bel as an encounter. His defensive numbers are tops, so the party will probably be beating their heads against a wall trying to even touch him with iterative attacks and abilities that require saves, especially spells. If permitted a full attack in melee range, he throws out stupid amounts of damage - easily enough to take out a PC in one round, power attacking.Unfortunately, melee is only of marginal utility here, as his mobility and other strategic options are abysmal. He wields 4 flails, but has no interesting combat maneuvers to attempt with all that weaponry. I don't know how your players do things, but a smart party will stay out of his reach, and as far as I can tell, Bel can't get at someone who is levitating, much less any form of flight, etherealness, gaseous form, etc. This will force him to use spell-like abilities, since he has no other ranged attacks. Of these,...
Thanks for the input. However, I would like to point out that this is for 3.5, not Pathfinder. I thought I made that clear in the initial post but upon review it seems like I had forgotten to mention that. Hence why the formulas may seem wrong.
Additionally, I'd like to thank you for pointing out some typos. His feats should actually be Multiweapon Attack and Improved Multiweapon Attack, I'm not exactly sure how I missed those typos.
I was thinking about "cleaning up" his spell list, as it were. His spell-like abilities are all according to the "how to build a god" entry in Deities and Demigods, so there isn't a lot of variation.
I hesitate to give him additional abilities, as he's to go up against a ECL 17 party and push them to their utter limits. I don't want to make the encounter super-fatal, because that is just no fun. Additionally, there are some outright beginners in my group that don't really prepare their spell lists intelligently, which lead to some pretty bad outcomes in combat.
I will probably give him fly 60 ft. (perfect) to help out with the whole "flying creature" thing, and clean up his spell list a bunch. I may also reintroduce his wounding effect, but I removed that because I feared he would be too lethal with it. I'll also remove the divine rank and just make some abilities inherent to his design (such as his Godly Realm, etc). I might reinstate his "divine rage" ability, as the rage flavor behind Bel is conveyed through his Belspawn and Bel-touched creature template...

Maeloke |

Thanks for the input. However, I would like to point out that this is for 3.5, not Pathfinder. I thought I made that clear in the initial post but upon review it seems like I had forgotten to mention that. Hence why the formulas may seem wrong.
Additionally, I'd like to thank you for pointing out some typos. His feats should actually be Multiweapon Attack and Improved Multiweapon Attack, I'm not exactly sure how I missed those typos.
I was thinking about "cleaning up" his spell list, as it were. His spell-like abilities are all according to the "how to build a god" entry in Deities and Demigods, so there isn't a lot of variation.
I hesitate to give him additional abilities, as he's to go up against a ECL 17 party and push them to their utter limits. I don't want to make the encounter super-fatal, because that is just no fun. Additionally, there are some outright beginners in my group that don't really prepare their spell lists intelligently, which lead to some pretty bad outcomes in combat.
I will probably give him fly 60 ft. (perfect) to help out with the whole "flying creature" thing, and clean up his spell list a bunch. I may also reintroduce his wounding effect, but I removed that because I feared he would be too lethal with it. I'll also remove the divine rank and just make some abilities inherent to his design (such as his Godly Realm, etc). I might reinstate his "divine rage" ability, as the rage flavor behind Bel is conveyed through his Belspawn and Bel-touched creature template...
Ah, so it's 3.5. I just assumed we were talking Pathfinder, what with the board we're on.
I think part of the problem is that you're trying to build this guy using the Deities and Demigods book. Its a funny resource for OMG POWER light reading, but it's terrible for designing balanced encounters.
If you want this guy to be a good fight, I'd recommend starting with a creature in the right vicinity, rather than building a god from scratch. I already hinted at it, but balors and pit fiends are right where you want to be, so they should be a good base to work from. I find that adding abilities to high level creatures like them isn't especially dangerous. As long as it doesn't actually giving them more actions, they can still only muster one set of attacks or spell per turn. Many of his divine abilities can really be relegated to your narrative- like does he need remote communication, remote sensing, and touch of Bel in his statblock, or can you just tell the story and use those as necessary?
Anyhow, in your position, I'd take a balor, then
-whip and vorpal sword
-fire aura
+2 arms (swap feats if necessary)
+4 flails (swap feats if necessary)
+PF advanced simple template (+4 to all ability scores, +2 natural armor)
+2 SR
+uses of base spell-like abilities
+all domain spells 1/day as 20th cleric
+domain powers at 1/day
and then maybe
+rage as level 20 barbarian (seems to fit flavor)
+fast healing 10 (just to ensure the party has to keep on the pressure)
That'll give you something like a cr 21 or 22 encounter, well-balanced to challenge a party, with more developed strategic options than just 'stand and swing'.

Kaushal Avan Spellfire |

Here's the rework:
Bel the Slaughterer CR 21
CE large outsider (chaotic, extraplanar, evil)
Init +7; Senses darkvision 1 mile, low-light vision, true seeing; Listen +38, Spot +38
Languages dark speech, all
Aura divine aura (DC 28, 10 ft), frightful presence (DC 28, 100 ft.)
DEFENSE
AC 39, touch 14, flat-footed 31
hp 360 (20d8+200); DR 15/epic and good
Resist electric 10; SR 33
Immune ability damage, ability drain, acid, cold, fire, energy drain, mind-affecting attacks, transmutation
Fort +23, Ref +20, Will +20
OFFENSIVE
Speed 60 ft. (12 squares), fly 60 ft. (perfect)
Melee +3 unholy adamantine flail +35 (2d6+15/19-20 plus 2d6 evil against good plus lacerate)
Melee four +3 unholy adamantine flail +33/+28/+23/+18 (2d6+15/19-20 plus 2d6 evil against good plus lacerate), +33/+33/+33/+28/+28/+28/+23/+18 (2d6+10/19-20 plus 2d6 evil against good plus lacerate)
Melee four slams +31 (1d10+12)
Base Atk +20; Grp +36
Atk Options great cleave, power attack, smite 1/day
Special Actions atrocities of war (DC 28), boneshattering blows (DC 30), control creatures (DC 28), devour soul (DC 28), impact weapons, inspire bloodlust (DC 28), lascerate, murderous momentum, summon servants, tangling chains, taste for blood, taste for death, unholy rage
Spell-like Abilities (CL 20th):
at will- animate dead, blade barrier (DC 24), blasphemy, contagion (DC 21), create greater undead, desecrate, disintegrate (DC 25), dispel good (DC 23), earthquake (DC 26), flame strike (DC 23), greater dispel magic, greater teleport (self plus 50 lbs. only), harm (DC 24), inflict critical wounds (DC 22), magic circle against good, mass inflict light wounds (DC 23), power word blind, power word stun, shatter (DC 20), summon monster IX (evil monsters only), telekinesis (DC 23), unholy aura (DC 26), unholy blight (DC 22)
1/day- gate, implosion (DC 27), power word kill, wail of the banshee (DC 27)
STATISTICS
Abilities Str 35, Dex 25, Con 31, Int 24, Wis 24, Cha 26
SQ alternate form, battlemaster, immortality, remote communication, remote sensing, touch of Bel, touch of corruption
Feats Cleave, Dark Speech, Improved Multiweapon Fighting, Greater Cleave, Quicken Spell-like Ability (telekinesis), Multiweapon Fighting, Power Attack, Weapon Focus (flail)*
Skills Bluff +31, Concentration +33, Diplomacy +35, Disguise +8 (+10 acting), Hide +26, Intimidate +33, Knowledge (history) +30, Knowledge (religion) +30, Listen +38, Move Silently +30, Search +30, Sense Motive +30, Spellcraft +30 (+32 scrolls), Spot +38, Survival +7, Use Magic Device +31 (+33 scrolls)
Possessions four +3 unholy adamantine flails
SPECIAL ABILITES
Portfolio battle, death, massacre, rage, war
Alternate Form (Su) As a standard action, Bel may assume the form of a male or female human, half-orc, or orc. This functions similarly to the polymorph spell, except that Bel does not heal when he changes shape. Bel gains the physical ability scores of the new form, but retains his mental scores and all of his abilities. Bel does not gain the exceptional, supernatural, or spell-like abilities of his new form, but he does receive any racial bonuses and traits that would be acquired.
Atrocities of War (Su) When Bel's body is destroyed, it explodes in a nebulous torrent of souls and bloody memories. All creatures within 100 ft. of Bel must pass a DC 28 Fortitude save or take 100 damage from negative energy. Even upon a successful saving throw, creatures within the burst still take half damage. Additionally, all creatures within 100 ft. must pass a DC 28 Will save or suffer 2d6 strength and wisdom drain from the terrible images that dance through their minds as the souls are released. This blast destroys all equipment Bel is carrying.
Battlemaster (Ex) Bel is considered proficient with all simple, martial, and exotic weapons, as well as all armors and shields, including tower shield.
Boneshattering Blows (Ex) Bel's terrible strength and skill with the flail means that whenever he scores a critical hit he shatters the foe's bones, forcing the victim to make a DC 30 Fortitude save. Failure indicates that Bel has shattered the creature's bones, inflicting 2d6 strength, dexterity, and constitution damage. In addition, the creature falls prone and cannot move or take non-mental actions, and is treated as paralyzed. Even upon a successful save, the victim still takes 1d6 strength, dexterity, and constitution damage and is stunned for 1 round. Unlike normal ability damage, heal can restore damage caused by boneshattering blows. The saving throw DC is Constitution-based.
Control Creatures (Su) Once per day, Bel may attempt to seize control of one giant, humanoid, or monstrous humanoid's body, as if by dominate monster, except it is not a mind-affecting ability (Bel seizes direct control over the creature's body). The creature to be affected must be within Bel's line of sight to be targeted. Once control is established, distance is not a factor and Bel remains in control remotely, even across planes and through wards or barriers (except those constructed by other deities). The subject is allowed a DC 28 will save to resist the effect and is allowed a new save if Bel commands the subject to do something against its nature. The saving throw is charisma-based.
Devour Soul (Su) Whenever Bel slays a creature with a melee attack, he devours its soul. The creature cannot be ressurected by any means (even miracle and wish do nothing) until Bel's body is destroyed and the soul released.
Divine Aura (Ex) The mere presence of Bel can deeply affect mortals, granting them resolve in the name of carnage. All of Bel's allies receive a +4 morale bonus on attack rolls, saving throws, and checks, while his foes receive a -4 morale penalty on attack rolls, saves, and checks. A DC 28 Will save negates the effect. Any creature that makes the save is immune to the aura for one day. Bel can choose and set the size of the divine aura as a free action, to a maximum of 10 ft. If Bel sets the aura at 0 ft. then it becomes effectively non-functional. This is a mind-affecting effect.
Domain Powers (Su) Bel gains the ability to use the domain powers of the chaos, destruction, evil, and war domains once per day.
Frightful Presence (Su) Whenever Bel attacks, charges, or roars, foes within a 100 ft. radius burst must make DC 28 Will saves. Foes within the burst, but not Bel's immediate target, become shaken for 3d6 rounds if they fail their saves. Creatures Bel attacks when it activates the ability become panicked for 3d6 rounds if they fail their saves. Foes who make successful saving throws are unaffected by this ability for one day.
Godly Realm Bel possesses a personal residence and fortress known as the Iron Citadel. It is here where he is most powerful and he possesses at least modest control over the environment of the Citadel. Bel may set the temperature of the fortress between -20 F and 120 F and fill the area with any scents and sounds that he sees fit. Sounds can be no louder than what 100 men could make, but he cannot create intelligable speech or harmful sounds. Bel's ability to create scent is similar.
Immortality (Ex) Bel is immortal and cannot die from natural causes. Bel does not age, and he does not need to sleep, eat or breath. Bel may be slain in magical or physical combat. Bel is not subject to death from massive damage.
Impact Weapons (Su) Any bludgeoning weapon that Bel wields has its critical threat range increased by one step as if affected by the feat Improved Critical.
Inspire Bloodlust (Su) As a standard action Bel may attempt to consume the minds of all creatures within 100 ft. with thoughts of war and violence. Creatures within the area must pass a DC 28 Will save or attack the nearest creature as though under the effect of an insanity spell. This is a mind-affecting attack. Creatures that pass the will save are immune to Inspire Bloodlust for 24 hours afterward.
Lacerate (Ex) When Bel strikes a creature with a melee attack, the blow leaves a horrid wound that bleeds profusely, taking 1 point of bleed damage per round for each wound scored. A creature struck multiple times takes multiple wounds. wounds can be removed when a creature receives magical healing, or with a DC 25 heal check.
Murderous Momentum (Su) When Bel drops an enemy and performs a cleave, he receives a +1 circumstantial modifier to damage rolls for each prior enemy he has dropped. For example, if Bel attacks a foe and drops him, he may cleave into the next foe and deal 1 additional damage with his weapon. If that attack drops the foe he cleaves into, he may cleave again at a +2 bonus. If Bel reaches a +10 bonus from ten consecutive cleaves, then he may move up to 60 ft. in any direction and continue the cleave. Moving like this constitutes as a charge and provokes attacks of opportunity. Bel may only charge once this way per round.
Summon Servant (Sp) Once per day Bel can automatically summon 4d10 dretches, 3d6 silent ones, 1d10 silent one witches, 1d10 silent one hunters, 1d4 belspawn, 1d4 hezrous, or one nalfeshnee, greater silent one hunter, marilith, or balor. This ability is the equivalent of a 9th-level spell.
Tangling Chains (Ex) Once per round, Bel may choose to make one of his attacks a tangling chains attack. The attack deals damage as normal and Bel may make a trip attempt against the target as a free action as the long, barbed chain of his flail wraps around the creature. Creatures cannot react to trip Bel if the trip fails.
Taste for Blood (Ex) Whenever Bel inflicts a wound with its lacerate ability, it becomes invigorated, gaining fast healing 5 until the end of its next turn. Thus, Bel will always have fast healing 5 provided it causes a wound each round.
Taste for Death (Ex) Whenever a creature dies within 100 ft. of Bel it becomes invigorated, gaining new strength. It gains a +2 sacred bonus to strength and dexterity, and a +1 sacred bonus on all saving throws. These sacred bonuses increase whenever a new creature dies, to a maximum of +8 to strength and dex, and +4 to saving throws. These sacred bonuses last for 24 hours before subsiding.
Touch of Bel (Su) Once per day, Bel may bestow the touch of Bel upon a living, willing creature. Through this touch, Bel channels its rage and lust for blood, stoking the blood of the recipiant and transforming them into something different. The touched creature receives the Bel-touched template, as detailed elsewere.
Only a humanoid, giant, monstrous humanoid, or magical beast may receive the template, provided they do not already possess the evil subtype. Once the transformation begins, it takes 24 hours to complete. For those 24 hours, the creature is wracked with a terrible pain that prevents it from moving as its body undergoes numerous changes.
Touch of Corruption (Su) Once per day, Bel may channel utter evil into a creature it touches, corrupting it and filling it with dark energies. Bel must maintain unbroken contact with the touched creature for one full minute in order to complete the process, so naturally only restrained or willing creatures receive the touch.
A creature that takes on the corruption gains the corrupted template, as detailed in the Book of Vile Darkness. The corruption takes 1d4+3 days to fully manifest, at which point the taint is irreversible. Before that point, it is possible to purge the taint with a miracle or wish spell.
Unholy Rage (Ex) As a free action, Bel may enter a state of unholy rage, becoming an utter killing machine. While enraged, Bel still maintains clarity of thought and may still use skills and spell-like abilities. Bel gains a +8 morale bonus to strength and morale bonus to constitution, and a +4 morale bonus to all saving throws. It also gains a -2 penalty to AC for the duration of the rage.
The rage lasts for a number of rounds equal to 3 + Bel's (newly modified) constitution modifier. Bel may only gain the benefit of rage once per encounter.
Changes: I cut back his 9th-level spell-like abilities of 1/day (comparing to the Balor). I added Boneshattering Blows, Impact Weapon, and Tangling Chains as partial analogs to a Balor's ability, as well as Atrocities of War to complement the notion of a divine aftershock following the death of a god. Additionally, lacerate and taste for blood combo nicely into a minor healing effect while requiring the party healer to keep the "tank" "topped-off" otherwise he'll bleed-out rather quickly.
Additionally, I designed unholy rage to just be a massive buff with no downsides (so he can still use his spell-like abilities while raging). This makes him incredibly lethal if he makes a full-round attack, on top of the 1/10 chance per attack that he will cause boneshattering blows.
Thoughts?

Maeloke |

Hmm... seems like you took my suggestions, but rather than adding powers to a balor, you added them to your demigod instead. Brutal :)
New spell list looks excellent, as does the improved mobility and such. I like the tangling chains ability, although it does get into the realm of free extra actions, which you may want to avoid. I commend you to the improved disarm/trip selection of feats, which will let Bel make good use of those flails and provide an option for you to softball your players with if he's thrashing them *too* hard with the weapon damage.
Taste for death *and* unholy rage might be a bit overboard for a baddie that's already rocking a 35 strength. Depends how many people are gonna die before he wades into the fight.
The raised DCs have caused me to look again at his divine aura, and it worries me a bit. Your group's fighters are looking at basically a -4 to every relevant roll, putting Bel's AC even further out of reach. If your group isn't the most tactically clever bunch, I can just see them sitting there in the grinder, unable to touch your fast-healing BBEG. I would probably eliminate the penalty-to-foes bit entirely; Bel spending an action to dispel some buffs is one thing, but being able to drop every melee party member by 4 levels of effectiveness for free is not really a recipe for player fun. He's already freaking tough.
Atrocities of war is... probably a TPK ability. Or damn near. Good for business if you plan on only the cleric making it out alive to resurrect the others, but figure that every low-fort character in the party is going to take the full 100 (never mind the ability drain), and injured fighters (notably, those who have taken a boneshattering blow) will probably fare no better.
You've definitely amped up the nastiness. Right now, if played intelligently, he could wreck a lvl 20 party with relative ease. Your party's success will depend on you using forgiving tactics. Play him savage, rather than smart, and you should be fine.

Kaushal Avan Spellfire |

That's the plan. Plus Death Ward should protect them from the more lethal part of Atrocities of War (the 100 negative energy damage). You're right about the Divine Aura, I'll have to play that one by ear.
Unfortunately, I've tightened my belt on his feats already and I'm not sure what I can give up for imp. trip (Weapon Focus [flail] is now a bonus feat gained from the War Domain). Dark speech can go, I suppose, it's mostly flavor anyway.
Thanks again for your help.

Maeloke |

That's the plan. Plus Death Ward should protect them from the more lethal part of Atrocities of War (the 100 negative energy damage). You're right about the Divine Aura, I'll have to play that one by ear.
Unfortunately, I've tightened my belt on his feats already and I'm not sure what I can give up for imp. trip (Weapon Focus [flail] is now a bonus feat gained from the War Domain). Dark speech can go, I suppose, it's mostly flavor anyway.
Thanks again for your help.
Best of luck; go give that party a run for their money :)