Decamillennial Hearthflame

Tier II · Burn · Mirror Dungeon 5

Affinity: Wrath
Shop price: 201

Base

Turn End: enemies with 3+ Burn Count activates Burn one more time (reduce Burn Count by 1)

How to get it in the Mirror Dungeon

From these events

More Burn gifts from Mirror Dungeon 5

Decamillennial Stewpot

Secret Cookbook

Purloined Flame

Unhatched Embers