Born in the contaminated basement waters where cleaning chemicals mixed with dissolved merchandise and synthetic materials, the Department Devourer emerged as the infection spread upward into the retail floors. It began by absorbing abandoned shopping carts and scattered goods, but quickly developed an insatiable hunger for entire store infrastructures. Each department store it consumes adds to its mass and intelligence, making it a constantly evolving threat that knows every product, every layout, every secret of commercial retail.

The Department Devourer appears as a massive, undulating mass of fused retail elements - mannequin limbs writhe alongside clothing racks, cash registers pulse like organs, and store signage flickers with corrupted electrical impulses throughout its body. It moves by dissolving walls and floors with acidic secretions, then absorbing the dissolved materials to grow larger and more complex. The entity can split portions of itself to simultaneously consume multiple stores, coordinating its feeding through a network of integrated security cameras and PA systems that have become part of its nervous system.

The Department Devourer serves as the ultimate consumer, literally eating the retail infrastructure that survivors depend on for supplies and shelter. It forces constant territorial retreat as entire sections of the mall become uninhabitable, transforming familiar shopping areas into alien landscapes of fused commercial horror.