OK, Shade already did something like this above, but I’m going to re-dissect some of the aspects of this guy, so that we can move discussion forward.
Dragon #248 said:
NO. OF ATTACKS: 3 or special
DAMAGE/ATTACK: 1d12+10/1d12+10/2d10+10 or special
So, claws were 1d12 base and bite was 2d10 base. Now, of course, the damage bonus for the bite would be +19 and the claws would be +9. the base damages could go a little higher than that of a standard dragon.
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DR 248 said:
Magically merged with the mountain known as Vstaive Peak, when Vore Lekiniskiy emerges, he only does so partially.
Vore Lekiniskiy attacks using his foreclaws and bite, or he can execute any of the special attacks described in the "Dragon" entry of the MONSTROUS MANUAL™ tome except those that require flight or quick movement - Vore Lekiniskiy is tied to the mountain.
Combat: When Vore Lekiniskiy emerges from the mountainside, his head and either one or both of his claws rip free simultaneously. He may be able to free more of his body, but it is thought he cannot bring more than half of it out at any one time. He can attack with both his claws and his bite in the same round.
Vore cannot hunt or move from the mountain, but he can emerge anywhere on the mountain in 2d4 rounds. He can retreat the same way and at the same pace. He can attack while retreating, but he usually retracts his head first, making his claw attacks at 4 until they return to the mountain.
OK, I’m thinking more along the lines of limiting his physical attacks to just claw and bite, plus things like the Snatch feat. As for his speed, I think that should be 0 technically, but he should have a Su ability that allows him to appear anywhere on the mountain and takes 2d4 rounds (maybe or maybe not provoking AoOs). Shade suggested mimicking the meld into stone spell for part of this effect.
Qwillion said:
In away him being part of the mountain reminds me of a dragon enslaved by a Genis Loci
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DR 248 said:
He seldom troubles with the power to automatically use geas, suggestion, or feeblemind on anyone trapped in his gaze, but this may change.
Make these SLAs?
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DR 248 said:
When Vore erupts from the mountainside, he causes an earthquake that forces everyone on the mountain to save vs. paralyzation or be thrown to the ground. The DM may allow modifiers to the saving throw based on how close the characters are to where Vore is erupting.
Shade suggested we could model this, in part, after the earthquake spell. We can also use some of the information on earthquakes in the DMG.
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DR 248 said:
Any character that sees Master Fire Worm ready for battle must save vs. spell at 4 or succumb to a fear spell.
Frightful Presence (Ex): Vore Lekiniskiy can unsettle foes with his mere presence. The ability takes effect automatically whenever Vore (attacks, charges, or leaps overhead?). Creatures within a radius of (240?) feet are subject to the effect if they have fewer HD than Vore. A potentially affected creature that succeeds on a DC X Will save (remains immune to Vore's frightful presence for 24 hours. – keep this part?) (On a failure, creatures with 4 or less HD become panicked for 4d6 rounds and those with 5 or more HD become shaken for 4d6 rounds. – keep this effect or substitute with another one? What’s the equivalent to the 2E fear spell?) Vore ignores the frightful presence of other draconic creatures. The save DC is Charisma-based.
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We’ll worry about his spell casting later after the rest of this stuff is ready to go.

that part might get pretty involved, but the rest of this should be resolved with more ease.