Magical Knots are strong magical items used to confine a creature or person. The only way to untie them is for someone to say " I sever this knot of my own free will," and blow on it. Once the knot is undone, strong magical energy is released and can be used to accomplish a spell. If all the knots are undone, the captive is free.
These knots where first used to imprison the demon Bahumat underneath the Forgotten Chapel. After that, they where used to imprison Muriel Taggert. Over the years, people untied some of the knots on Muriel's rope so that they could get a wish. Stan Sorenson untied one so that she could change Seth Sorenson back to normal after he was attacked by the fairies for changing a fairy into an imp. After that, Seth and Kendra untied her last knot so that she could change Ruth Sorenson from a chicken back to normal. Once Muriel escapes, she uses the same method to release Bahumat's knots; making wishes for him to grant her, each wish releasing a knot and eventually releasing Bahumat.