Sword of Light and Shadow
"And here we have the Sword of Light & Shadow. This paradoxical weapon contains both divine and necrotic energies. When wielded with precision, it can deal a significant blow to your foes. Forged from the melted remains of a sword of darkness and a sword of light, a guild of ancient dwarves created it in the hopes of making a weapon that could stand against both fiends and celestials. They got the necrotic burst of energy right, however, they discovered that the radiant energy side of things could sometimes release an unexpected effect. This unique sword is priced at 200 gold pieces."