Mission

A mission (or quest) is a set of objectives given to the player to complete.

Missions by game

 * Missions in Deus Ex
 * Missions in Deus Ex: Invisible War
 * Missions in Deus Ex: Human Revolution (walkthrough article)
 * Missions in Deus Ex: The Fall (walkthrough article)
 * Missions in Deus Ex: Mankind Divided (walkthrough article)

Terminology
In Deus Ex and Deus Ex: Invisible War, missions are phases of the single player campaign. Missions are not explicitly named or otherwise identified in-game, but the term "mission" is used in internal game files, pre-release development documents, and official strategy guides to denote the respective phases of the story. Mission names are given in their official strategy guides, but are not used in-game.

In Deus Ex: Human Revolution and Deus Ex: The Fall, the term "main mission" refers to mandatory missions, while the term "side quest" refers to optional missions. In Deus Ex: Mankind Divided, the side quests are instead called "side missions."