User blog comment:ShiroDes/Huge issue need help (PC)/@comment-17054927-20131006072040

There is something new:

If your world generates with Crismon biome, you are going to get 3 NEW hardmode ores. If your world generates with Curruption you are gonna get Cobalt, Mythril and Adamantite. Then just make sure you are deep underground. Try using a spelunker potion.