This is a very minor change to the original works. I like the cube, but didn't want to have to open and close it to get victims in and out. I just cut the "top" flat in Solid Works. Flip it over and it's a sealed cube ready to absorb PCs. I don't have any transparent filament at the moment, I may have to test print with glow in the dark.
EDIT 1/27/18: Finally got some clear ABS. The overall print ended up better than the glow in the dark version. I print this top down with support, it's less support than printing it the way it is modeled.