After i played Cave 2, and rolled for my resources, i got a metal bar, a new high end resource for forging, but there are no new Blueprint shops, so i guess there will be new levels!
Might also be one of the cave blueprint drops that requires it – I’ll be starting cave 5 soon, and I’ll let you know if I come across any that use metal bars! :)
@yjemer, finished all the Caves and saw that some Blueprints require it, but i think it still could also be good for some new levels, because at he end of Cave 5 it says New Caves Coming Soon!