The Root Queen is a level 40 boss at the end of the Delga Temple. She can be spawned by activating six switches in the proper order. Each switch corresponds to a note on the tonal scale, as shown in the picture. The correct order of the switches that must be pressed is: Do -> Re -> Mi -> Fa -> So -> La.
The switches are in the following pattern, so players know what order to press them in.
5(So) 2(Re)1(Do) 4(Fa)