"The sorcerous mist you see here exists in both reality and irreality. It was created by Nyrissa to guard her

"The sorcerous mist you see here exists in both reality and irreality. It was created by Nyrissa to guard her dominion from invasion. It will hurl you between reality and irreality, and all about, preventing you from reaching the heart of the House and other secret nooks. But I've brought something that will help you. Take this lantern. Light it and hold it high, and the mist will have no power over you. But if you need to step from reality to irreality or back, then hide the lantern and let the mist carry you."