How does Dagger of Darts damage work?

Witch Doctor
1

Since skills base their damage on “weapon damage” and not “primary skill damage”, I was wondering why the carn build was using all effects that provide a bonus to primary skills, as the witch doctor’s personal damage is so insignificant compared to that of his summons (they have additional damage multipliers and there’s a bunch more units).

So I was doing some testing with a single fetish that was hitting for about 1 B. By putting on the dagger of darts, I would expect (as the legendary power says) for the fetish to increase his damage by a factor of 5, so he should hit for about 6 billion. Instead he’s suddenly hitting for about 18 billion. One item to increase damage output by a factor 18. That seems pretty unreasonable, even for this game.

Then I put on the depth diggers. Since they increase the damage of primary skills, and fetishes aren’t a primary skill, my intuition would tell me that they should have no effect on my fetish damage. Instead, he started hitting for 35 billion damage, meaning he’s somehow benefiting from my primary damage. I imagine it’s the same case for the primary attack gem.

So, what’s going on here? What stacking multipliers are in effect here?

2

In the case of Carnevil, the majority of damage is coming from your fetishes’ darts, nor your own. It’s rather unique in that the darts you proc benefit from not only your pets’s damage bonuses but also your darts damage bonuses as well. Anything that makes your darts do more damage makes your fetishes darts do that much more damage as well.

I don’t know the exact formula for the damage calculations, but I’d suspect that the dagger, the pants, +% darts damage, and the simplicity gem are separate multipliers, rather than all of them being added together. They’d also get similar benefits from % poison damage, the enforcer gem, +fetish army damage, and the Zuni 6-piece bonus.