Did you notice if the stone to flesh spell removed? sometimes spell have an effect without any wording. For example the black flail when you use it raises your mres correctly but does not tell you it did so.

Hydra would be very difficult for solo warrior (unless you have an insanely high ac/dr). Your best bet is to level up at the timelord (you can go to lvl 54 there I believe). Get yourself a roomer friend that will make life at the hydra much easier.