Quoted from phishrace:It wasn't advertised as a skill shot, but Fireball had one almost 10 years earlier. It was very strategic (valuable) and not easy to do without practice. If you have to play Fireball in a tournament, by all means try to get in some practice time first to practice the skill shot.
Fireball also had multiball, zipper flippers and a spinning disk. If ever there was an LE EM, Fireball was it. It ruled the arcade around here for years.
Fireballs original documentation refer to the opening shot as the "top ramp skill shot feature"