Used thick cardboard and glued together with a heat gun.
Large balls are polystyrene, and the smaller ones are just 'super balls' with the bottom cut off.
The turrets are just cut thinly with a razor blade, not completely through, and curled around and glued.
Spray painted it, and glued on the door silhouettes.
Took about 8 hours to do in total.
Sorry for the lack of detail in the video but it was a last minute consideration.
Ask me questions in the comments and I'll help you.
![](https://s2.save4k.ru/pic/UqY5u_Ove3I/maxresdefault.jpg)