Styrofoam was definitely used but to a much smaller extent then cardboard boxes. Used cutup cereal boxes and pencil crayons to make some of my computer screens and radar monitors then glued them to the cardboard boxes. I remember my mom getting upset with using her good scissors to cut up the cardboard. Really dulled them. so then we started to use steak knives to cut boxes.
I also used my desk as mountain and used the desk cabinets as inside the mountains bases.
I never did real water though for the boats. Always a unzipped blue sleeping bag we had.
Jungle was always either a aquarium back drop picture or moms weird house plants in the big planters
I also remember using a lot of plastic ice cream pails with openings cut into them as storage sheds for vehicles.
Man i miss those days...I should totally do a cardboard base just for the fun of it.
Anyways I do wonder if my opinion on the 83 hq being the best will change once I actually put some figs on my terrordrome. As a kid that was the one I wanted the most and now that I have it I have yet to actually put a figure on it and i've only had it for a year and only out for a week before it got put in storage.. Maybe during the Christmas break.
