Cybele

From the Super Mario Wiki

Cybele is a sorceress in Mario and the Incredible Rescue. She is an old woman with glittering green eyes, living in a cottage in a forest she appears to own. She owned The Book of Spells which Bowser stole during the events of the book. When she first meets the brothers, she has a hood on and tells the brothers that they have to give her something so that she may help them. Luigi gives her a coin that he found in Kero Sewers. Then, she helps Mario and Luigi in saving the Mushroom Kingdom and Princess Peach from Bowser. She tells Mario that to stop Bowser and his spells, the brothers must gather six Mushrooms scattered around the Mushroom Kingdom. She then gives Mario a blue pouch to carry the Mushrooms he collects during his adventures. She also gives him an envelope which she tells Mario to not open unless there is no hope left-it turn out to be a letter which helps him fight Bowser by telling him that the six Mushrooms have special powers. It is presumed Mario returns her book after he gets it but it is not confirmed as the book ends when Mario gets the book back and it ends with Cybele smiling far, far away in her forest.