In the Murkmire Malevolence, Matthew and Devona were contacted by the Golden Vault handler Meera Raheer for a mission that was ultimately called off. Not really understanding what it meant to be a thief, Matthew joined a heist alongside Margaret Pearl, Leilatha Vencaryn, and Rasmus O'Dranith, growing quite close with the team.
After spending a few weeks proselytizing to an extremely confused flock, the group was called to action. They were tasked with returning the Murkmire Stone, secretly an egg containing a deadly Abberation, to Doctor Cassee Dannel. During a gala at the Cliffsunder Museum of Natural History, they planned to steal the stone by cart, using a Draft Horse named Marx to carry it across town under the guise of "Cliffsunder Party Supplies."
During the period before the heist, Matthew learned that many across the continent worshipped his god, but under the name "Umera", and everything clicked as to why he had experienced such little success in his gospel. He had better luck proselytizing to the guards of the museum, but took it too far, and was kicked out for seeming to be on mushrooms; unknown to Matthew, he forever altered the life of Clarc Pendergilt-Vanth.
At the gala, the mission as a whole went awry for him; the party believed he could fly when they drew up their plans, and he did not tell them otherwise. Caelas Helefir, the incumbent Port-Lord of Cliffsunder, unexpectedly crashed the party in search for his brother. Matthew ultimately ended up in a dungeon belonging to after accidentally making it seem like he worked for Ulrë Helefir; in exchange for his life, the cleric convinced Caelas that he could work for him. Somehow, Matthew ended up an unwilling hitman on the payroll of the Helefir family.
With his status compromised and location unknown, Matthew was considered to be an inactive agent by the Golden Vault.