World of Warcraft Patch 11.1, "Undermine(d)," introduces the long-awaited Goblin metropolis of Undermine, a location steeped in WoW lore.  Beyond the bustling city itself, players can uncover a trove of secrets and nostalgic references, particularly for fans of WoW Classic's Season of Discovery.

One such treasure is the Undermine Undershirt transmog.  This distinctive purple shirt, previously unobtainable, is a direct replica of the one worn by Pix Xizzix, a vendor from the Classic Season of Discovery.

Acquiring this transmog involves a charming Easter egg hunt.  Players must locate a Sewer Cheese beneath a grate in the Vatworks, near the Side Street Sluice delve.  This grants a buff, “Cheesed to Meet You?”, enabling interaction with a Hungry Rat. The rat, in turn, offers a Tarnished Undermine Real, a currency familiar to Season of Discovery veterans.

This Tarnished Undermine Real can be traded with Pix Xizzix, now located on the second floor of the Port Authority building in Blackwater Marina. This triggers a unique dialogue option, culminating in the acquisition of the coveted Undermine Undershirt.

The reappearance of both the Tarnished Undermine Real and Pix Xizzix evokes a sense of nostalgia for players who experienced the Season of Discovery. In Classic WoW, these Reals were crucial for acquiring catch-up gear and unique toys, with Pix Xizzix serving as the primary vendor for these items.

This isn't the only hidden gem within Undermine.  Players can also discover Greexit Coarsebub, a vendor tucked away in an alley south of Slam Central Station.  This vendor offers unique armor pieces – the Bruiser’s Helm, Spaulders, and Tabard – with color schemes tied to the player's current Cartel of Undermine contract.

Beyond these specific secrets, Undermine is brimming with Easter eggs and references, from nods to pop culture icons like Batman and the Teenage Mutant Ninja Turtles to numerous callbacks to WoW's rich history.  These hidden details provide a rewarding layer of discovery for players exploring the newly unveiled city.