Hellfire Weapon
Source: Baldur's Gate - Descent into Avernus
Weapon (any), uncommon
This weapon is fashioned from infernal iron and traced with veins of hellfire that shed dim light in a 5-foot-radius.
Any humanoid killed by an attack made with this weapon has its soul funneled into the River Styx, where it's reborn instantly as a lemure devil (described in the Monster Manual).