User blog comment:EpicBananaMan/i dont know wat to do :(/@comment-24169653-20140125224821

My first suggestion would be to get a dictionary or at least attempt to learn that which is proper grammar, then retry asking a question that at first was random gibberish in Hieroglyphs and what I can only assume to be a question about mythril not appearing.

All joking aside, Mithril isn't the only 1st option of ores to spawn in Terraria after destroying an altar. I believe your world would be blessed with either Cobalt or Palladium, Mythril or Orichalcum, and Adamantite or Titanium. Mithril not showing simply means that world doens't produce Mithril.