The player views the action from a first-person perspective and guides Duke through a linear sequence of Washington-themed levels. Objectives include finding access routes, activating switches, collecting keycards, surviving ambushes, and reaching the exit.

Duke can run, strafe, jump, swim, use environmental objects, and fight with firearms and explosive weapons. Secrets, health items, armor, ammunition, and temporary power-ups reward exploration. The DOS release is primarily a single-player expansion campaign; its level progression and combat follow Duke Nukem 3D conventions.

Search rooms and side passages before leaving an area; keycards and switches are often placed away from the main route.

Conserve explosive ammunition in confined spaces, use cover against hitscan enemies, and check interactive scenery for hidden supplies. Save before major set-piece encounters and before entering unfamiliar teleporters.