Chasing Oathgold

There's more to Oathgold than just it's shine, |n. It's also strong an' can't be tarnished or corroded. I've been hurryin' here because I wanted to make a test of that. My friend Varndra keeps hearin' reports of a strange monster just outside the Mourkain ruins. They're callin' it the Corrosive Horror, an' they say it can't be killed. Those who've fought seem to be winnin', but when the creature is weak an' they strike its heart their weapone get ruined. I think Oathgold is the key to killin' it, an' I hope you'll help me test that theory. Go find the Corrosive Horror, and weaken it. When it's in its weakened state, strike it with the Oathgold Pick. I think that should finally kill it.

Find the Corrosive Horror near the Mourkain Ruins. Use the Oathgold Pick on it and then attempt to kill it. Return to Chiri Smalldeep at Reekmarsh Camp when you've killed it.