Originally posted by Engletroll:

I’m playing with my son and we keep on getting killed because he over estimate his skills. I’m trying to get him to take it slow. He wants to go into the Plains to get black metal. But his skill is around 10 to 15.

Even if he gets black metal, he can't use it. You need to kill the Mountain Biome boss in order to refine black metal into a usable form.