Greaves Lightning Oil is a major business within Dunwall, and a producer of refined whale oil heavily used by the city's modern technologies as well as manufacturing whale oil refill stations and oil tank dispensers.
The company was founded when Ebenezer Greaves established his own slaughterhouse on the Rudshore Waterfront, the Greaves Whale House, and then later the Greaves Refinery to process the raw whale oil. As one of the leading producers of whale oil it became extremely profitable, capable of employing "over 300 workers, not including the children who filled minor, and often tragic, roles," at its operating peak. In the later days of the company, a system of pressure valves was installed to link the refinery to the Rothwild Slaughterhouse, allowing a faster way to transport the raw oil for treatment.
However, when the river barrier broke, both the Whale House and the Refinery were abandoned, with the latter becoming a haven for assassins, weepers, river krusts and even looters interested in the oil tanks abandoned on the premises. It is possible that the whale oil shortage broadcast by the Propaganda Officer is due in part to the collapse of Greaves Lightning Oil, which left other companies such as the Rothwild Slaughterhouse to refine their oil themselves.
- Originally, "Greaves Lightning Oil" was called "Greaves Lighting Oil", and this name was used in pre-release images of advertisements for the business, but it was changed when Dishonored was released.
- A pre-release poster for the company uses the month of August on its chart, instead of using the in-universe calendar and the Thirteen Months.