2 set bonus only has Lightning Attack. It has 0.5 sec cooldown per monster. This hit applies 5 seconds Flame Vulnerability debuff on mob. Each time a flame attack procs from 4 set bonus hits the mob while debuff is active, mob will get hit by extra lightning attack proc. This extra lightning attack proc can’t apply debuff if its triggered because of vulnerability debuff. But it counts as a hit and has a chance to trigger flame/lightning attack that can apply vulnerability debuff.
4 set bonus only has Flame Attack. It has 0.5 sec cooldown per mob. This hit applies 5 seconds Flame Vulnerability debuff on mob. Each time a lightning attack procs from 2 set bonus hits the mob while debuff is active, mob will get hit by extra flame attack proc. This extra flame attack proc can’t apply debuff if its triggered because of vulnerability debuff. But it counts as a hit and has a chance to trigger flame/lightning attack that can apply vulnerability debuff.
6 set bonus: Each time a mob gets hit by lightning or flame attack procs you gain 1 stack. More enemies you hit, more times you hit makes you get stacks faster. After you reach 30 stacks lightning and flame procs from set will deal double dmg.
2 set only Lightning procs, vulnerability effect of 2 set doesn’t work until you get 4 set bonus.
4 set Flame + Lightning procs can cause multiple extra Flame/Lightning procs Vulnerability.
6 set after 30 procs you gain a buff that doubles damage of set procs. Doesn’t increase your character’s skill damages.
Proc damage has a fixed formula and it is affected by your Attack Power, Crit Rate, Crit Dmg, Flat Dmg increase buffs. Engravings like Cursed Doll - Grudge - Keen Blunt - Adrenaline etc. works. Berserker, Sorceress, Gunslinger, Wardancer synergies increases your proc damage since you gain Attack Power, Crit Rate, Crit Dmg, Flat Dmg increase buffs from those synergies. Heavenly Tune etc. sup Attack Power increase buffs also works. (Bards takes this since it increases proc dmg and solve mana issues.)
But directional dmg increase engravings, synergies doesn’t increase proc damage. Hit Master engraving doesn’t increase damage of procs because it’s counted as directional damage engraving and it’s not used together with Charming Set. Gunlancer - Deathblade’s has %9 head/back attack dmg and %3 all dmg increase. %9 dmg increase doesn’t increase set proc dmg. But %3 all dmg increase does. Also gunlancer armor reduction debuff on mob will also work.
Flat damage increase - Crit rate increase card sets works. Like Lostwind Cliff set, Light of Salvation set (even though element changes to Light it doesn’t decrease set damage procs and instead increases it.)
Charming set attacks has a certain chance to proc per hit. More hits you have, more procs you will have. That’s why you use skills that have too many hits and take tripods that increases skill hit count.
You must continiously attack and apply as many hits you can on enemies all the time to keep uptime on procs.
Proc attacks can cause more proc attacks.
Bleed Rune - DoT effects might cause procs too. Haven’t tested this.
Proc attacks happens as small AoE attacks. More mobs inside it, less dmg it deals. Damage can reduced to 20% at most and can’t get lower than 20%. I am not sure how much reduction it applies per mob it hits.
For example
Against boss it deals 1m dmg per proc when there are no other mobs around.
If proc aoe hits 2 mobs at the same time it deals 800k dmg to both mobs.
If proc aoe hits 5 mobs at the same time it deals 200k dmg to per mob.
If proc aoe hits 20 mobs at the same time it will still deal 200k dmg to per mob.
or
It can deal 1m to single mob, 500k per mob to 2 mobs, 250k per mob to 4 mobs etc.
I hit mob with a single basic attack
This triggered lightning attack and applied 5 sec Flame Vulnerability debuff. This lightning attack proc counts as a hit and has a chance to trigger 2 or 4 set attack proc.
- If that lightning attack procs a flame attack, this flame attack hits twice because of vulnerability. First flame attack hit changes Flame Vulnerability debuff to Lightning Vulnerability debuff. Second flame attack deals damage but doesn’t refresh debuff duration. First flame attack from set bonus and 2nd flame attack from Flame Vulnerability counts as 2 seperate hits total and both has a chance trigger 2-4 set attack procs.
- If that lightning attack procs a lightning attack, that proc refreshes 5 sec Flame Vulnerability debuff and has a chance to cause another Flame/Lightning Attack proc
- If that lightning attack doesn’t proc another attack, it stops set attack procs caused by set attacks itself and you need to hit mob again.
Because of this you might trigger 0 or infinite procs with each hit. You repeatedly hit boss with fast multiple attack skills. Your attacks causes procs, procs can cause more procs…