There is an element behind certain doors in the elemental rooms in the League of Magic, they are locked. If one were to open one of those doors, you'll fall, drown, burn or be incinerated. There is a door that is locked up tight, along with a partner. This door's element would destroy anyone who dared to see it, it is used by dark wizards for their own purposes, it is also the father of hatred, which the element is the evils of the universe
Talroc the Great to Orcul about Hades' element in the League of Magic
Evil is the element of Hades. It was created when the universe began as it was good (Death) & evil (Hades & Glaux). Hatred is a known evil that was created by Glaux. Evil is also used in magic, which is known as dark magic. By classification of the League of Magic, the act of committing evil or use of dark magic is considered dark larceny.