3-D Zapper © 1982 US Games Corp.
An unreleased 3-D space game prototype.
According to programmer Todd Marshall: 'There was a 3-D space game that I was working on (referred to as 3-D Zapper in company memos). There was a debate at JWDA about 3-D. For some reason, Jim Wickstead was thinking about making a 3-D game. I don't remember why. When I quit, I was thinking of presenting the 3-D game idea and the second of those carts has a 3-D gun and 3-D enemies and hit detection.'