My first thoughts were: What the hell is this? It's no unique attack modifier or what? Do they even stack?

The answer actually is: Yes, they do stack. But I don't feel like trying it out without proof that it could make sense.

I imagine those players wrongly assuming: getting 3 items with 35% chance to proc gives guaranteed procs (this is obviously NOT true)

There seems to be no existing mechanics thread about stacking Savage Mace, so I decided to make my own.

People don't always realise but the Savage Mace proc 'mechanics' are similar to other items, just some basic probability calculation. Let's assume "1" are procs and "0" not, then an attack with 2 Savage Mace can have 4 possible outcome: P(00) = 0.65², P(01) = 0.65*0.35, P(10) = 0.35*0.65, P(11) = 0.35²

Thus the chance of having 1 proc: P(01 or 10) = 0.65*0.35 + 0.35*0.65 = 45,5%

Oh well, I didn't actually calculate them myself but let Excel do the magic. So for the geeks, these are the results:

Pouring them in a graph gives this:

The chance the target got mini-stunned (thus chance at least 1 of the maces procced) is what matters most. It's in bold in the table and in the graph the total height of all colors together. The only difference between the amount of procs (diff colors) that I would say is the extra bonus damage.

**Having at least 1 proc: comparing 1 Savage Mace (35% duh) to 2 Savage Maces (57.75%) is still acceptable at +22.75% increase. But getting a 3rd (72,5%) and 4rth (82.1%) would only increase the chance by +14.8% and +9.6%.**
My personal conclusion is that it might actually be worth getting a second Savage Mace in certain very situational situations. I anticipated much worse results. But I'd never go for a 3rd or 4rth one, there are always more useful ways to fill those valuable items slots. Although that's certainly not mechanics related and shouldn't get discussed here, but you're free to start the conversation elsewhere ^^