1| Your alignment has to be completely "good."

2| Hire the mercenary in Twinblade's Camp, bring him to the chapel & sacrifice him at midnight.

3| The easiest way to know it's midnight, is because 你 pay the mercenary 金牌 every hour. Once your money bag pops up 展示 你 he's getting 更多 gold, wait for it to disappear & talk to the man closest to the entrance of the chapel.

4| 你 know for sure you've got Skorm's Bow when the man says, "Your desire for my evil influence is gratifying. 你 will go far."

It's seriously as simple as that. Trust me, I've tested this method out several times just to make sure it wasn't some kind of weird game glitch. I don't think it is personally, because whenever I use this method it always works & I get it on the very first try every single time.

{By the way, I play it on the Xbox, so I'm not sure if it'll work the same if 你 play the PC version.}