Among the ancient ancestral spirits who accompanied Saint Veloth and the Chimer into the promised land of Morrowind, the four Daedra Lords, Malacath, Mehrunes Dagon, Molag Bal, and Sheogorath, are known as the Four Corners of the House of Troubles. These Daedra Lords rebelled against the counsel and admonition of the Tribunal, causing great kinstrife and confusion among the clans and Great Houses.
Malacath, Mehrunes Dagon, Molag Bal, and Sheogorath are holy in that they serve the role of obstacles during the Testing. Through time they have sometimes become associated with local enemies, like the Nords, Akaviri, or Mountain Orcs.
Molag Bal is, in Morrowind, the King of Rape. He tries to upset the bloodlines of Houses and otherwise ruin the Dunmer gene pool. A race of monsters, said to live in Molag Amur, are the result of his seduction of Vivec during the previous era.
Sheogorath is the King of Madness. He always tests the Dunmer for mental weakness. In many legends he is called upon by one Dunmer faction against another; in half of these stories he does not betray those who called him, further confusing the issue of his place in the scheme of things (can he help us? is he not an obstacle?). He is often associated with the fear other races have of the Dunmer, especially those who, like the Empire, might prove as useful allies.
Mehrunes Dagon is the god of destruction. He is associated with natural dangers like fire, earthquakes, and floods. To some he represents the inhospitable land of Morrowind. He tests the Dunmer will to survive and persevere.
The worship of these four malevolent spirits is against the law and practice of the Temple. However, the Four Corners seldom fail to discover those greedy, reckless, or mad enough to serve them. By ancient Temple law and custom, and also by imperial law, the lives of witches and warlocks are forfeit, and Imperial garrisons join Ordinators and Buoyant Armigers of the Temple in tracking down and destroying these foul covens in the wilderness refuges and ancient ruins where they conceal their profane worships.