Pretty self explanitory. I was wondering why only some Caterium and some Iron?! are under those Boulders. At least i only found Iron and Caterium beneath them. Why not place a Boulder on all the Advanced Resources? Speaking of:
(i dont think it makes sense to block Sulfur obviously)
- Raw Quartz!
This way you cant just go for Nuclear Technology without making Bombs for example and it would require you in some Cases to have Gas Masks and Explosives combined to get to the more advanced resources which i personally would like because it feels like i need to do more to get those ,,better,, Items and work a bit more for them then just getting Iron which is - and in my opinion - should be easy to get. ( i dont see the point in putting boulders on Iron)
As always this is just a Suggestion and ment for Brainstorming.