Deus Ex is a 2000 action role-playing game developed by Ion Storm and published by Eidos Interactive. Set in a cyberpunk-themed dystopian world in the year 2052, the game follows JC Denton, an agent of the fictional agency United Nations Anti-Terrorist Coalition (UNATCO), who is given superhuman abilities by nanotechnology, as he sets out to combat hostile forces in a world ravaged by inequality and a deadly plague. His missions entangle him in a conspiracy that brings him into conflict with the Triads, Majestic 12, and the Illuminati.

An immersive sim (simulation) is a video game genre that emphasizes player choice. Its core, defining trait is the use of simulated systems that respond to a variety of player actions which, combined with a comparatively broad array of player abilities, allow the game to support varied and creative solutions to problems, as well as emergent gameplay beyond what has been explicitly designed by the developer. This definition is not to be confused with game systems which allow player choice in a confined sense or systems which allow players to easily escape consequences of their choices.