Lamashtu

The patch of midnight darkness takes a look at the assembled champions then seems to nod at Agis.
You may call me Lamashtu. I'm a spirit from a land far to the East where the twin great rivers flow. I'm a servant to the goddess Ereshkigala, the great lady beneath the earth, guardian of the Seven Gates. I have some power over the forces of Death and Destruction.
Looking at the fighters in the group and hearing Agis' suggestion she nods.
I can call forth the Fires of the Netherworld to employ against my enemies. If bestowed upon a weapon, each blow will echo with the screams of lost souls and a portion of your enemy's life will be cast to the void. I can bestow such power several times but I prefer not to expend too much power that will be needed later-I will enchant four weapons of your choice, preferably those belonging to the best meele fighters here.

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Sorry, my mistake-the name is Lamashtu. (got confused with another character)
Lamastu employed her Unholy Aura to grant those benefits to the group.
She can now cast Weapon of Energy (twin, felldrain) on four weapons. This will make them do an extra 2d6 sonic damage and 2 negative levels per hit.