I have made a new building material; devilsteel. It's almost 6 times as strong as plasteel, and costs 6 times as much, with an additional 6 devilstrand required per block. It can only be crafted one block at a time at a stonecutter's bench.

This allows you to have a very long but not (too) over powered end-game, it will require loads of trading, or mining/growing, while seriously growing in wealth. But your fort will be much harder to penetrate, allowing you to survive very tough raids. But the repairs will take a lot of time, 6 times longer. Everything comes at a cost.

Tell me what you think. Maybe interesting material to hold a rimworld.gallery contest with one day?