Outcast is a 3D third-person (with an optional first-person view) action game with adventure elements. In search of five sacred relics, the protagonist travels through the five continents of Adelpha (plus one tutorial island). Each land has its own landscape (mountains, lakes, forests), populated areas, as well as dozens of minor problems - small quests that the hero is required to solve. Most Talans populating the world can be conversed with about a variety of topics. A large portion of the game consists of finding key characters and performing quests for them; some of these are optional, though most must be completed in an adventure-like linear fashion in order to advance the plot. Cutter is free to travel between the continents using special portals.

Apart from exploration and completing quests, Cutter will also fight many guards and creatures. At his disposal are six futuristic weapons (railgun and others); ammunition for those guns is scattered around and can also be produced by mixing items. Aiming help is provided in the form of laser sights. Sneaking up to the enemy and punching him out silently is also possible. Gadgets such as a holo-decoy can be used to help Cutter gain the upper hand in combat. The player character can also jump, climb, swim, dive, crawl, and ride a local animal known as Twon-Ha for faster travel.