Elements of these almost forgotten fan productions shaped many aspects of the game. The "Technical Manual" itself decided the main functions of the Federation Heavy Cruiser, and what other Federation ships looked like. A set of blueprints (probably those drawn by Michael McMaster in 1975) showed the Klingon D7 as having "more" phasers than the Heavy Cruiser, and disruptors mounted on the engines. The latter became a common feature of Klingon shipbuilding, and the former led to the idea of less powerful phasers for the Klingons. The same blueprints also stated that an older, slightly inferior version of the D7, the D6, was what was sold to the Romulans, and the D7/D6 dichotomy has been at the heart of the Klingon fleet in the game ever since. Two of the novels gave mention of a phaser being mounted on shuttlecraft. This was included, as much to give a reason to use shuttles as anything else. This proved to be the wedge that allowed the introduction of fighters to the game; a feature popular with many players, but also led many to believe that "Star Fleet Battles" was no longer "Star Trek".