A.W.O.L. is a first-person, mil-spec shooter developed using the Build engine (Duke Nukem 3D, Ion Fury), specifically a modernized version of the Build Engine based on the "EDuke32" source port which allows for modern hardware acceleration and modern controls while retaining the original 2D pixel sprite graphics. Originally conceived as a passion project by a small Build Engine mod team in the early 2000's, the game was in development for almost two decades before finally being released for free on Steam in September 2022.