In the extended tooltip for Void Cleave’s ‘Vorpal Force’ node (more damage per stack of bleed), it states that the effect scales with ignite instead if you have the ‘Riftflame’ node (50% base damage to fire, adds fire tag, among other effects). Testing against a training dummy with ~20 ignite stacks (15 should give a maximum boost of 120% more melee damage), I noticed no significant damage difference between 0/4 and 4/4 points in the ‘Vorpal Force’ node. I also tested the interaction with one point in ‘Hellish Chasm’ (full fire conversion) and observed similar results.
Tests were done with a completely unspecialized Void Cleave (aside from nodes mentioned above) in full offline mode.
Thanks!