G'aufs knows that it is a hydra, and that it heals really, really fast.
For this combat it does not matter if the claw disappears because G'aufs would have coughed it out if it is still there (25 Fort save), but I would still like to know.
Round 574
The hydra ignores the gas (rolled 18 Will save). G'aufs can breathe again in round 576.
Round 576
The hydra starts making grunting noises (9 Will save). G'aufs can breathe again in round 579.
Round 577: The hydra growls in frustration at not being able to attack G'aufs.
A draw is declared at the end of round 577.
Round 578
A ten-foot long, sloth-like animal with black and white banded fur waddles into the arena to 60N100E.
Next in round 578 for Chaotic Evil is a frostfell ghost (Frostburn).