You can train Firemaking via the Wintertodt minigame using the
Fighting the Wintertodt provides item rewards scales to your Woodcutting, Mining, Fishing, Farming, Crafting, and Herblore levels, and xp scaled to your Firemaking level. You need level 50 Firemaking to challenge the Wintertodt, and each attempt requires food to heal yourself from the Wintertodt's attacks. You will automatically use lower quality food first. The speed at which you challenge the Wintertodt increases with a higher Woodcutting level, and the food required is reduced for every piece of the pyromancer outfit you have equipped in your skilling setup, or other items of warm clothing.