Critolus Masse, a Rodian male, held the position of underlord within the criminal organization known as the Darkwalker gang. This gang operated on Naboo during the era of the Galactic Civil War. During 1.5 ABY, he met his death at the hands of a spacer who served as an officer in the Royal Naboo Security Forces. This occurred during the rescue operation to free Karl Eckener, who was being held captive by the Darkwalkers in their cave.
Critolus Masse was featured as a non-player character within the video game Star Wars Galaxies. This game was a massively multiplayer online roleplaying game created by Sony Online Entertainment and brought to the public by LucasArts. The game was shut down on December 15, 2011. Critolus Masse's inclusion in the game was a part of the "Legacy Quest", which was introduced with the "Publish 25" update, also referred to as the "New Game Enhancements," released on November 15, 2005.