I think he meant having the 3,5 mm jack in a phone.

I played it occasionally but, as you said, it wasn’t very interesting game for young children. I guess it was interesting only subconsciously (the vivid dreams I mentioned in the other comment). Maybe it would have been fun game if I were an adult at the time.

We didn’t really have arcade in our town but there were some coin-operated games around. I think it wasn’t very long period of time they had Polybius but I remember playing it occasionally during that time. I was quite young so I didn’t fully understand the gameplay and can’t really recall any elements of it anymore. Only thing I do remember is I used to have vivid dreams about it when I hadn’t played it for a while. That sort of made me interested to play it again every once in a while. Though I must have been terrible at that game so I don’t know why I even tried it that many times.

I didn’t really thought about it when they had changed the machine to different one. I would rather play the Street Fighter II or whatever they had put there instead because it was much easier game to understand. There have been occasional dreams I’ve had much later in my life about this game but other than that I don’t really think about it. Sometimes after having that kind of vivid dream I do think for a while that it would be nice to give it a try again but I don’t know if they have the game anywhere or if it’s possible to emulate via MAME.