From Destinypedia, the Destiny wiki
The Factory Brig is a massive Fallen Brig deployed by the House of Salvation in the Empire's Fall mission Sabotaging Salvation. Guardians are tasked with preventing the Fallen from producing advanced weaponry and sabotage their industry by blowing up Brigs.
Initially, a Factory Walker was deployed to battle the Guardian, but quickly was crushed by the Factory Brig to initiate the final boss encounter. The Brig, however, would be destroyed and the sabotage of the factory be completed.
Their attack patterns and behaviors mirror their regularly sized counterparts, only increased in lethality due to their size.
List of appearances