Under a Killing Moon dramatically shifted the gameplay of its predecessors in the series by fully utilizing interactive 3D environments. The player controls the protagonist Tex from a first person perspective. The virtual world allows full freedom of movement, and as such allows the player to look for clues in every nook and cranny. It was also the first Tex Murphy game to stray from the traditional adventure game dialogue format of providing options that showed exactly what the player's character would say. Instead, descriptions of the dialogue choices were given, providing some mystery to what Tex would say.