Where can I get the Radiant Sword Hunter badge?

Excuse me, I was wondering if you could assist me with a query. I'm on the hunt for the elusive Radiant Sword Hunter badge, and I'm having some difficulty locating it. Could you please enlighten me on where I might be able to acquire this badge? Perhaps it's a reward for completing a certain quest or challenge? I'd be most grateful for any information you could provide.