A Facilitator is an oil, also called Weigh anchor by Briar, which helps mages to begin an important or difficult task of magic. Rosethorn blended carnation, lotus and myrrh oils in a certain way to strengthen their properties of strength, purification and the penetration of obstacles were at the height of their power. Rosethorn had also taught Briar how to make this oil during his first winter at Winding Circle. When the oil is used drops of it are put on the center of each palm and on the forehead between the user's eyes. Briar and Rosethorn used the Facilitator when they had to refresh the old medicines in Urda's House during the blue pox epidemic.