I believe most AOE weapons only triggers carnage once, making them worse than normal weapons just because of lower base damage, at least for carnage. I tested Wahai Pōraga on dummies, but I really couldn't make sense of the messy combat log. Does it trigger carnage multiple times?

Are there other weapon effects that interacts with carnage?

By the way, does the Static Charge damage of Lord Darryn's Voulge benefit from Hot Razor Skewers? I can't see the penetration numbers in the logs, but it seems to be always underpenetrating.

Carnage can trigger multiple times, but if it does in a short time frame (for example when Swift Flurry/HBD  procs) the game will tell you something like "similar effect already applied".
So it doesn't really "stack" like it did in PoE1.

Weapon effects which get triggered not only by weapon attacks but on spells etc., too (universal), should also proc on Carnage hits (or kills):

• Scordeo's Edge: Double Strike
• Sungrazer: Return Orbit
• Engoliero do Espirs: Cruel Blade and Blade Feast 
• The Twin Eels: Breath of Life
• Azure Blade: Wrong Place, Wrong Time
• Sanguine Greatsword: Thirsty Blade and Parched Blade
• Oathbreaker's End: Found Guilty/Innocent
• Dire Talon: Tooth and Claw
• Aamiina Legacy: Slayer of Beasts
• The Spine of Thicket Green: Purge Decay
• Wicked Beast: Wild Heart
• Amaliorra: Ash and Dust
• Amaliorra: Innevitable Decay
• Whispers of Yenwood: Soul Cutter
• Xoti's Sickle: Soul Reaper

List originally composed by @Constentin Lévine

 

I think Sungrazer has the best interaction here. The occurrence of the AoE should increase significantly with Carnage if you attack tight groups of enemies. Maybe here a hybrid dual-wielding setup (Sungrazer + one-handed ranged weapon) could make sense to dish out as many Sungrazer-attacks (with Carnage) as possible?

Hi, I don't remember whether Grave Calling works with carnage and its procs or it was "nerfed" at some point. If not, then it should be great versus hordes of vessels.

Grave Calling has no interaction with Carnage.