There are sixteen different game modes in Xonotic, including classic modes like deathmatch and capture the flag. In order to unlock more game modes, players must complete different levels of game play. To score points, players must kill enemies using futuristic weapons while completing objectives. The gameplay is very fast paced, due to players being able to move at high speed and jump erratically. While the basic concept is inspired by other games of the same genre, there are several unique elements. Emphasis is placed on movement and player physics, with a focus on gaining speed, jumping great distances, and conquering the level geometry. This is done with classic techniques including strafe jumping, bunny hopping, and rocket jumping. Weapons have special abilities such as multiple fire modes, which increase the tactical options available to the players.
The game features a futuristic aesthetic, with maps set in high-tech environments and in space. The game runs on the DarkPlaces engine and thus supports bloom, dynamic lighting and shadowing, offset mapping, and high dynamic range rendering.