I know that the LE killed by the Black is dead now. But I'm talking about the alpha one. Also, there's more. Here, I'll list it in audibly visible bullet points...

• Ignores Invincibilities and Resistances

• Increases Damage Output by an insane amount

• Increases the chance of any Secondary effects the Weapon has so that they will always happen (kind of like Serene Grace)

• Any luck-based weaponry will be modified so that the most favorable outcomes for the user will have a higher chance of happening

That's all I've heard so far. But the recipe, so I've heard, involves a HUGE load of Grist, even by God-tier standards, and a whole boat-load of various Legendary Artifacts to get its Prototype, and THEN you need to use Time Shenanigans to turn it into its completed form.