The Elf-scout Pothlorn was wounded in an encounter with Stone-trolls while scouting Ost Thondol.
'There were many wolves on the path, and they became ever more maddened the nearer I came to Ost Thondol, which lies on the height right above me. They would not pass the foot of the hill, however, so I pressed on... only to encounter Stone-trolls in the ruins above.
'I sensed something else there, as well, but I know not what it was, for the trolls were too many for me, and I was forced to retreat. They were nearly my death.
'If you wish to be of true aid to Elladan and Elrohir, head up the hill to Ost Thondol and seek the source of the evil here. Whatever it is, even the wolves fear it....'
The ruins of Ost Thondol can be found atop the hill, north-west of Pothlorn.
Pothlorn asked you to search the ruins of Ost Thondol for the evil he sensed during his battle with the Stone-trolls.
The worm-wight is in the ruins of Ost Thondol, north-west of Pothlorn's hiding place.
You should attempt to destroy the worm-wight, which appears to be leading the trolls of Ost Thondol.
Pothlorn is hiding among the rocks at the base of the hill, south-east of Ost Thondol.
You should return to Pothlorn and let him know what you discovered within Ost Thondol.
Elladan is at Thorenhad, north-west of Pothlorn's hiding place.
Pothlorn told you to return to Elladan and tell him what you discovered.