“ In the days of old, before the dominance of humanity, the giants were the supreme rulers of the world and their crafts were considered to be the best. These beings venerated the god of the forge above all others and their swords and armors were the best that could be had even in the days of their decline. A hero seeking a masterwork sword might have to voyage long and hard to find a surviving giant smith or cache of rare and valuable giantcraft weapons.”
“ You find a patch of edible funghi. They taste well and all, no ill effects. UNLESS you consume some beverage, even 3 (three) days after eating it. Then you become really sick with pains, vomiting, all the fancy stuff. As a gift or good meal, it could be a cruel joke or to make sure the heroes spend their time focused on the mission. And the fine soup you had in the inn yesterday could have some in.
(Inspired through a real-world fungus. Was really used to cure alcoholism.)”
“ An alloy of iron and iridescent meteoric metal, also known as shadesteel. Weapons forged of this metal cause gangreneous infections almost instantly and sometimes the victims becomes a shambling zombie after death. The material is very vulnerable to fresh water which will cause it to corrode and eventually melt in a period of hours to days.”