Foamcore, plastic, foam stickers, paint, etc.

Cobra's secret Springfield hideout! From inside the base, Cobra can operate hidden and undisturbed while conducting evil operations against G.I. Joe! A fairly innocuous exterior contains things that might subtly give away whats inside - like the retinal scanners next to the door! Inside the warehouse contains all the evil gadgetry Cobra needs for surveillance and night operations.

I in essence made this playset to have somewhere neutral for Joe and Cobra to fight. The bases always indicated a major attack - if Joe or Cobra show up at the Tdrome or HQ its a major battle. I wanted to make a dio of a small skirmish and this fit the bill just right.