Thanks to Glissen being 3-star, it doesn't trigger a rare drop animation. So even though I have already looted 2 Glissen weapons (wand and talis), I have no idea where I got them. Each time I only realized when I'm back in Central and cleaning out my inventory.
I've seen on Reddit that someone got a Glissen drop in Mt. Magnus. Where I have also been briefly for the regular daily task. But I have not seen someone specifically say they got their Glissen drop in the exploration zones.
So where did you get your Glissen drop? And are you 100% sure about where it dropped?
I'm planning to stash away 2 of each Glissen weapon and I would hate to keep farming in zones that simply won't drop them.