Gameplay Journal #2 — Engines

Travis Kosier
3 min readJan 26, 2021


The second entry in this series focuses on game engines, and how Overkill Software — formerly Grin — have used, and continued to use their in-house game engine, known as Diesel — in increasingly further departures from the game the engine was originally designed for, the 2001 racing game Ballistics. In this instance, Overkill’s most popular recent game, Payday 2 continues to use the Diesel engine- and indeed, have drawn some comment over its continued use by fans and players of Payday 2. Particularly, some fans have remarked upon the irony that one of the weakest parts of Payday 2’s gameplay experience is driving — a mechanic first added into the game well after release and featured only in a handful of the game’s nearly one hundred missions — considering the game engine’s origins as a driving game engine. While the validity of these complaints is a matter of debate, it nonetheless demonstrates the great lengths to which Overkill as stretched and adapted their Diesel engine, to the point where its original purpose has largely been supplanted by its — generally well-received — first person shooter gameplay. Based on Lowood’s definition of a game engine as “a reusable platform for efficiently developing several games” (Lowood, 206), and in terms of extensibility — the Diesel engine is a clear success. All of Overkill’s games since 2001 have used some version of the Diesel engine — and they have largely been first or third person shooters, featuring a variety of mechanics, including driving, and generally are regarded as competent executions of the genre.

In terms of how the Diesel engine works, information is hard to come by as the engine is closed source, being Overkill’s in house game engine. What is known is that the engine was first used on Ballistics, as stated above, and went through many iterations, with versions 6 and 7 of the engine being used in Overkill’s ports of Tom Clancy’s Ghost Recon Advanced Warfighter 1 and 2 for PC, both of which ran on other engines for console: the Unreal Engine 2, and YETI engine respectively, meaning there is presumably some compatibility between these two engines and Diesel. Payday 2 and Raid: World War II both run on the second generation Diesel engine. Moreover, Overkill has purchased the Valhalla game engine for use in its future VR games, but does not plan to abandon the Diesel engine for the aforementioned two game titles, and plans to use it again. Adding to this the fact that a substantial Payday 2 modding community exists — both tied to the steam Workshop, and existing on sides suck as and — suggest continuing to work with the engine is easy and desirable enough it won’t be going anywhere any time soon.

Anyone interested in seeing Payday 2 for themselves can watch this video by LetsPlay:

All rights to the video and its content belong to LetsPlay, and I am not related to or endorsed by them, nor are they endorsed by me.

Works Cited:

Deger, A. C., Guins, R., & Lowood, H. (2016). Game Engine. In Debugging game history: A critical lexicon. Cambridge, MA: The MIT Press.