I was in shadow priest spec and received this from the 5x weekly timewalking chest. Horrible proc on casting damage, this shouldn’t be available for non-melee classes.
The proc is a cantrip and not part of the items budget. It doing anything at all is already performing better than an equivalent ilvl weapon with equal stats. It’s also an intellect weapon so I don’t know why you think it should only be available to melee classes.
To your point I think the ability is to add some flavor and not to be super powerful; however, it is confusing. The text is vague and just adding clarity would be a good step.
That is literally the BiS weapon for shadow priests so IDK what you’re talking about.