Hi Richard,
Spoilers below. You have to have had a good memory or take good notes
like I did for my walkthrough (I haven't posted it yet - waiting for
Simon's corrections). Do you remember what Demelza scratched out way
back in the Cursed Crypt? Or the hint Agathena gave you in the Cursed
Crypt? I'll give out hints one by one below if that didn't jog your
memory. Good luck!
Cheers,
Chris
Spoiler below
Hint #2: Think 'cat'
answer below if you need it
Hint #3: '3 1 20'