856: Fang smiles a toothy smile and casts cat's grace (requires verbal) and flies to 80e.
857: Fang casts bless (V) and flies to 20e.
858: Fang casts doom (V) and flies to 80e. The worm is unaffected.
859: Fang does not successfully cast resistance (20%), but flies to 20e + wingover.
This whole time the worm just waited at 50N60E, while making that noise.
Round 860: As Fang approaches, the worm bites him with an AoO(rolled 48) for 25-10=15 points of damage. The worm then grabs Fang in its mouth (70 vs. 41 grapple). To complete his charge, Fang bites the worm back (rolled 38-4+1+2=37) for 23 points of damage, but no Con drain (rolled 33 Fort save). The worm has 397 HP remaining.
The worm chews on Fang for 31-10=21 points of damage, then swallows him (56 vs. 45 grapple). Fang takes 8 points of acid damage from digestive juices.
With his darkvision, Fang can see a whole lot of smaller worms in the big worm's stomach. Some of them try to burrow into Fang, and Fang cannot withstand them (rolled 34 Fort save), taking 7 points of Constitution damage.
Fang has 113 HP remaining, and his Constitution is down to 12.
Fang is first in round 861. Is he going to try to cut his way out using his sharp natural weaponry, or try to climb out of the stomach back into the mouth?