Firebranch

You touch a weapon and ignite it in living flames that count as magical. The weapon deals an additional 1d6 fire damage on a hit and sheds bright light in a 20-foot radius. Undead, demonic, infernal, fiends and other creatures from the lower realms take additional +2 damage. The flames do not harm you or your equipment.

At 4th level, the fire damage increases to 2d6 and undead, demonic, infernal, fiends and other creatures from the lower realms take additional +3 damage. At 6th level, the fire damage increases to 4d6. At 9th level, the fire damage increases to 6d6, and the weapon can set creatures on fire for additional 1d6 damage per round for 3 rounds.

The enchantment persists on the weapon regardless of who wields it for the duration.