In Break-In At Bleak End, Merben Ordri Fizzlehide Pennyluck had convinced Don Coriander to lend him men and funds to rob the Alabaster Palace prior to a noble party. The operation went horribly, resulting in a gang member's death; in response, the fairy had Merben beaten and tied up in a demiplane of fairy magic. Coriander sent a letter out to Nessa Nina Quickpick Rumbauld Pennyluck informing her of grandson's imminent death. She arrived with three former members of the Whistledrop Crew to beg for Merben's life.
After negotiating, Coriander sent Nessa Nina, Mercy, Ellenor Breatham, and Punmiri Tel-Phaeun on a mission to Farrozandmar. In exchange for the key, he would let Merben live and give them a small cut of the treasure behind the Undermire Dwarf-Door. He had set up Hollyhock Barrowes with the information that the thieves would be arriving, and to come up with a plan to break into Bleak End. After a successful heist, they returned from Aone Island with a tracing of the Dwarf-Door Tattoo Key, and were willing to accompany the Don as he broke in.
The campaign ended in disaster. After securing passage through the Faeriefort, Coriander led his force to the Undermire Dwarf-Door and used the copied key-mark to open it. The Fold had anticipated his move and prepared an ambush. Beyond the door, Coriander discovered not only the legendary treasure hoard, but also Vex, Volition, and other agents of the Fold waiting for him. He fought fiercely, Polymorphing into a massive serpent and repeatedly throwing himself into danger, but was badly outmatched. The Glitterati suffered catastrophic losses as the battle collapsed into chaos.
During the retreat, Coriander was nearly killed before being saved by Ellenor, and he returned the favor by turning her invisible to save herself. As the vault's Wild Magic defenses triggered a cave-in, the surviving fairies carried him to safety while much of his organization was left behind. Roughly ninety Glitterati members perished in the failed assault, and Snapdragon was separated from him the chaos, shattering the gang's strength in a single day. Though Coriander survived, the dream that had driven him for decades ended in ruin, leaving both his organization and his ambitions broken beneath the Undermire.