In terms of extremely minor one-off characters, He Who Was was very cool. I was sad when he didn’t show up in act three. Just a random Shadar-Kai warlock of the Raven Queen chilling in the Shadow Cursed lands, delivering warped justice to the dead, and collecting their tormented memories and emotions to sustain his queen.

He Who Was

I’ve never once seen this NPC and I’ve played through 7 times now. Where is he? Just a general area so I can go wandering.

Yeah, as the other commenter mentioned, wander around north of the Shadowed Battlefield waypoint, make sure to explore all the nooks and crannies at the edges of the map, you’ll find hus campsite eventually.