Worm That Walks Final Boss Advice

[Brolof]

I'm using a Worm That Walks Cleric of Urgathoa for the final boss of a large dungeon, for a party that can range from anywhere from 10 to 12. I'm just concerned it's too weak or too strong, once I add in some enemies to fight along side it. So, what do you people think? I'm thinking maybe 4 or 5 CR 9 or 8 enemies to fight along side this guy, for the final fight.

Worm That Walks Cleric of Urgathoa:

CR 14
Human Worm That Walks Undead Lord (Cleric) of Urgathoa 12
NE Medium Vermin (Augmented)
Init +4; Senses Perception +25
Defense
AC 30, Touch 20, FF 27 (Armor +10, Dex +3, Deflection +2, Natural Armor +2, Insight +5)
HP: 120 (12d8+24)
Fort +14, Ref +12, Will +17
DR 15/-, Fast Healing 14; Immunities Disease, Paralysis, Poison, Sleep
Defensive Abilities: Worm That Walks Traits
Offense
Spd 20ft
Melee: +1 Unholy Scythe +16/+11 (1d10+9/x4), Slam +8 (1d4+2 plus grab)
Special Attacks: Channel Negative Energy 10/day (6d6, DC 22), Discorporate, Squirming Embrace (3d6+6, DC 16
Domain Spell-Like Abilities
8/day--Death's Kiss
Cleric Spell's Prepared (CL 12, Conc +17)
6th--Create Undead*, Harm x2 (DC 23)
5th--Slay the Living (DC 22)*, Wall of Stone x2 (DC 20), Boneshatter (DC 22), Major Curse (DC 22)
4th--Enervation (DC 21)*, Air Walk, Poison (DC 21), Blessing of Fervor, Greater Magic Weapon
3rd--Animate Dead*, Blindness x2 (DC 20), Bestow Curse (DC 20), Contagious Zeal
2nd--Ghoul Touch (DC 19), Grace, Unliving Rage, Desecrate x2
1st--Cause Fear (DC 18)*, Detect Good, Moment of Greatness, Obscuring Mist x2, Protection from Good
0--Detect Magic, Create Water, Mending, Read Magic
Domain: Undead
Statistics
Str 18, Dex 19, Con 14, Int 10, Wis 20, Cha 18
Bab +9, CMB +11 (+15 on grabs), CMD 27
Feats: Command Undead*, Spell Focus (Necromancy), Extra Channel, Improved Channel, Channel Smite, Greater Spell Focus (Necromancy), Heighten Spell, Undead Master*, Extend Spell, Diehard*
Skills: Knowledge (Religion) +15, Perception +25, Sense Motive +28, Stealth +9
Languages; Common, Orisiani
SQ; Death's Embrace, Corpse Companion, Unlife Healer
Combat Gear; Headband of Mental Prowess +2 (Charisma/Wis) + Phylactery of Negative Energy, Belt of Giant Strength +4, +4 Breastplate, Ring of Protection +2, Amulet of Natural Protection +2, Cloak of Resistance +4, +3 Scythe

[Selvaxri]

There's a PFS scenario with a WtW as the big bad that i've been meaning to run, mostly to little avail.

Spoiler:

You Only Die Twice

That said, why is his initiative only 2 with a dex of 19?

All in all, it should be an interesting fight, especially if the Big Bad starts the fight in it's "swarm-mode"

I think it'd be more flavorful for the Cleric to have Bleed as one of it's prepared spells, as opposed to mending.

Don't forget about Scrolls/Potions/Wands for your army to use.

[Brolof]

I forgot to update it when I applied the Worm That Walks template.

[Dastis]

Definitely some minions to go with him. I would use some undead he made. Preferably debuffers/healers. Also he probably needs some more HP

[Azothath]

the CR should be APL+3 for a tough fight, maybe APL+4. Undead are usually tough so APL+3. You also have to assume that the PCs will know it's undead. It also depends on how min/maxed the players are. You might want to think about options to add low CR critters to adjust.

The NPC should have Unhallow, Desecrate and a few other area type spells in effect to dampen challenges. A shrine to his goddess is also needed.

some clerical spells to look at;
5th: Charnel House, Caustic Blood, Darkvault, Sum Mon 5(Babau, Ankylosaurus, lg Earth Elemental, Cloaker, Shadow Mastiff), Unhallow(Protection Energy Fire to all crtrs).
6th: Create Undead(gasts, ghouls, mohrgs), Sum Mon 6(Dire Tiger, hg Earth Elemental, Succubus).

on CR (if 2CR10=12, then CR12+CR10=CR13)
CR12 BBEG + CR10(or 3 CR7s, or 4 CR6s) is about CR13
CR14 BBEG + CR12(or 3 CR9s, or 4 CR8s) is about CR15

- - some monsters - -
exoskeleton template on vermin ('skeleton' vermin undead) CR varies but low
Apallie CR2 captured children?...
Hungry Flesh CR3
Shadows CR3, Greater CR8
Doppeldreck CR5
Glacial Ooze CR6
Livestone CR6 columns mixed with caryatid columns...
Skeleton host corpse (or zombie) CR varies with swarm
Rot Grub Swarm CR7
Mohrg CR8
Gashadokuro CR13

[Azothath]

if you have him summon undead things, you'll have to make up a list of critters. Also see;
Unhallowed Creature template (+0).
simple corruption template: ghoulish creature (+1).
Taxidermic Creature template.
Verminoid Creature template.