To make the most of our damage, shouldn’t go with Cold damage? Maniac (Fire) will give an increase to all Frenzy damage as dibs including Side Arm (Cold). Fire elemental will increase Maniac but it won’t increase Side Arm. Whereas Cold element will work hand in hand with Maniac and Side Arm.
I understand that, but according to D3planner, Cold is the only element that will increase the damage of every Rune. I’m guessing this is the because it factoring the increased damage of Sidearm.
Normally when a skill gains all runes, all its secondary effects should be converted to the element of the specific rune you choose to put on the skill bar, one exception is Vyr Archon which is determined by the highest element bonus on items.
Currently D3planner seems to use the highest element bonus on items to determine and calculate Frenzy’s damage with Undisputed Champion equipped no matter what rune is chosen, and I’m not sure if that’s correct.
From my tests maniac rune’s buff (25% DIBS) is always included in the damage calculation, so you probably want to double check. https://i.imgur.com/Y6IGVTl.png
As you can see from the picture above, sidearm damage is buffed by 25% DIBS and fire element bonus I put on bracers even though I chose Smite rune.
The biggest reason to go with Cold Damage is that Azurewrath is likely the best off-hand weapon for this build (because of the freeze chance), and if you take that, you’re automatically taking +Cold%. So, unless you want that roll to be wasted, it makes sense to stick to Cold.
I should also mention that sidearm doesn’t account for a whole lot of your damage. 300% weapon damage per hit, 25% proc chance, so an average of 75% weapon damage per hit. In comparison, regular Frenzy plus the Bastion chain does 2420% weapon damage per hit, so Sidearm hits are only increasing your damage by around 3%.