Of the three common types of spirits:
Fire burns nature
Water quenches fire
Nature feeds on water
In case you wanted to play in-universe rock-paper-scissors.
Magnolia (runes): [Scanning all drives . . .]
This outbreak of whispers is carried by nature spirits, so it gets to be stamped out by fire mages.
Magnolia: That’s all the infected out. We can begin clearing the area. The only possible risk left . . .
Bramble: Magus Persil is SO COOL.
Fire mage #2: She’s going to be Minister of Prophecy one day, you watch.
Magnolia: . . . would be if someone new had wandered into the area who was unusually susceptible to being infected very quickly.
Rowan: This is the library, all right! So why is it closed?