I made up all the information, hope that's ok, or that my ideas can be combined with any existing lore.Geldegwset
Man, now that's an interesting monster. All the information I could find was very vague about the appearance and lifestyle of the monster. Did you find some source of more myths somewhere, or is the detail from artistic liberty?
I think the damage mod on your attacks is off. Unarmed strikes are light weapons, my math says it should be +7. The thrown rocks aren't normally two-handed weapons, so they should be +7 as well. The melee attack should be +12 as far as I know.
You misspelled nonlethal a few times in there.
The unarmed damage is with power attack included, since i figure that's how they would fight, with wild swings. With only one attack that's pretty much always your best option anyway, so it should be written as standard, as far as i'm concerned. But i can write a note of it, of course.
Many giants (including this one) have an ability called rock throwing where you get to throw larger stones and do it two handed. It specifically says in the ability that they usually add 1 1/2 times on these attacks.
I'll change the spelling, of course.