A bruma kindling is obtained by using a knife on a bruma root, granting Fletching experience appropriate to the player's level. The Fletching experience given is equal to 0.6 times the player's Fletching level.
It is used to burn the braziers, found in the four corners of the Wintertodt's prison, to drain the Wintertodt's energy, granting Firemaking experience appropriate to the player's level. Bruma kindlings give approximately 27% more Firemaking experience than using bruma roots on the burning brazier. The exact amount of experience is 3.8 times the player's Firemaking level.