Okay, had this sitting around on my computer for a while, so I'm not sure which creature I originally began to modify to get the base of the stats [which is what I do. When I have an idea, I try to find a creature with similar stats and whatnot, and then go from there, changing what I then feel like changing] so I don't remember where I got the 4d6 bit attack from. Still, one of my friends had mentioned a creature that stole souls and used them to its advantage. He never finished the creature and since I like the idea of using souls, I decided I would create my own version, and here it is.
Note: I have not used this creature yet and don't know how well the abilities will work out, but hopefully, I'll insert him into my Ravenloft campaign, either as a pawn or opponent of Strahd.
10d8+90 (154 hp)
23 (-1 size, +14 natural), touch 9, flat-footed 23
Bite +14 melee (4d4+5/19-20)
Bite +14 melee (4d4+5/19-20) and 2 claws +12 melee (1d8+2)
10 ft./10 ft.
Improved grab, Paralyzation Breath, Stomach Stasis, Swallow Whole
Darkvision 60 ft, Life Stealing
Fort +7, Ref +7, Will +7
Str 21, Dex 10, Con 29, Int 14, Wis 14, Cha 18
Diplomacy +17, Hide +13, Intimidate +17, Kn (Planes or local) +15, Kn (Undead) +15, Listen +15, Move Silently +13, Sense Motive +15, Spot +15, Survival +15
Cleave, Improved Critical (bite), Multiattack, Power Attack
A chaotic evil-aligned plane
10 [though this can increase due to the number of souls]
Always chaotic evil
11-15 HD (Large); 16-30 HD (Huge)
"Moans and screams sound from ahead of you. As you cautiously approach, a blackened hairless figure steps into view. This creature stands tall above you and though most of it's form is fairly gaunt with tight muscles, the stomach of the creature is massive. Though the creature has long claws at the end of its arms, the shock-white jaws of the creature seem the greater threat as it opens its gaping maw. As it does so you, the moans become louder and you realize with a start that the sounds of pain are coming from within the creature itself."
Paralyzing Breath (Su):
This breath is consists of the stomach juice inside the Sjal Tuv. Three times per day, the Sjal Tuv can take the juices inside and spit them out, an action similar to that of puking. This is a fifteen foot cone and creatures in the area must make a Reflex save DC 24 or be paralyzed for 2d4 rounds.
Stomach Stasis (Su):
A creature swallowed by a Sjal Tuv must make a Fortitude save DC 24 or be paralyzed by the Sjal Tuv's stomach acids until the creature is freed. The stomach acids, although they paralyze the creature, do not prevent it from feeling pain nor do they stop the groans and screams of pain coming from inside the Sjal Tuv's Stomach. If a creature stays inside for an entire rest period, the creature gains rest as if it had had a normal night's rest [gaining a number of hit points equal to its HD].
Life Stealing (Su):
If the Sjal Tuv successfully swallows a person, it can then begin to steal their life forces, gaining 1 hp per person inside it's stomach. So if it has swallowed three people and is holding them in stasis, the Sjal Tuv would, when activing its Life Stealing ability, gain effectively Fast Healing 3. The Sjal Tuv is limited by the amount of fast healing by the number of creatures inside it. It can only benefit from this if the creature swallowed is at least of Tiny size. Activating this ability is a Move Action.
Soul Power (Su):
If a creature dies because of the Life Stealing ability, the suffering for that creature has not yet ended. His soul is taken in by the Sjal Tuv. One side effect of this ability is that a character cannot be brought back to any means until the Sjal Tuv is killed. Souls circle the Sjal Tuv, protecting it. Each soul lasts for 1 day per HD before they disappear. Together, the souls grant the Sjal Tuv a Deflection bonus to its Armor Class and Saves equal to the number of souls circling the Sjal Tuv, or the Sjal Tuv's Charisma modifier, whichever is fewer.
Soul Sweep (Su):
To use this ability, the Sjal Tuv must have a number of souls protecting him equal to 1 + his Charisma modifier. Each round, the Sjal Tuv may make an extra attack with each soul greater than his Charisma modifier. Thus an average Sjal Tuv has a Charisma modifier of +4. If the Sjal Tuv has 5 total souls circling it, it can make one additional attack per round. This attack is at the Sjal Tuv's attack modifier and is considered a Touch Attack. A soul deals 1d4 damage per hit and can only make a single attack each round.
Sjav Tul gain a +4 racial bonus on Hide checks in the dark because of their black skin. However, for each soul within their stomach, because of the moaning and screaming, they gain a -2 circumstance penalty on their Move Silently checks.
No one knows where the Sjal Tuv came from. Most suspect experimentations of Necromancers, but those people tend to be confused about the truth of the Sjal Tuv, believing it to be Undead instead of an Outsider, who also frequently use souls. Other speculate that numerous groups of malevolent souls band together to create the Sjal Tuv, but others mock those claims because if that was the case, then the Sjal Tuv wouldn't be physical in form.
The truth is probably closer to the fact that while some Demons trade souls and others use them for creating powerful items, some Demons have learned to absorb them into themselves and use them for their own personal power. These Sjal Tuv, "Soul Stealers", are probably similar to these Demons without actually being Demons themselves. They are not a part of the Blood War and in fact care only about the souls of others. They need the souls not only to protect themselves, but also to survive. They do not eat and in fact do not swallow anything but living specemins. Though they would prefer not to, in dire times, they will in fact, eat animals. People may not believe that animals have souls, but Sjal Tuvs have learned that any living creature with an intelligence has a soul they can use.
Some particularly clever Sjal Tuvs have managed to create a base of power for themselves and use the surrounding area as a virtually unlimited supply of souls. They tend to eat what they need to while keeping several people locked up for when danger approaches. Those who live in a castle and have guardians will eat the souls when pesky adventurers first announce their presence.