Invisible Man
This NPC can be found in
Stormheim (27), Broken Shore (13), Krasarang Wilds (9), Suramar (5), Throne of Thunder (4), Niskara (3), The Violet Hold (3), Icecrown Citadel (2), Kun-Lai Summit (2), Stormwind City, Unga Ingoo, Shadowmoon Burial Grounds, UNKNOWN.