Hi there everyone,
here are some test results on Coincidental Combustion I’ve done. I’m not a math guy but I’m pretty much sure I’ve got the this part right.
So, here we go:
Whenever you shoot an enemy with a non-explosive weapon, you have a 7% chance per level to deal bonus Explosive damage. The bonus damage is based on weapons damage.
That was the description, this is how it actually works:
On proc it results in +115% PURE splash damage (Radius) based on your weapons .GunDamage which is boosted by explosive bonuses, but not grenade damage bonuses. It gets boosted by One Last Thing which is [SpecialMults]? in the formula. [ElementBonus]? are explosive damage bonuses from .Skills, .Relic, .OZ kits.
Final Damage = (((Base * (1 + .GunDamage)) * 1.15 CC) * [SpecialMults]? * [ElementBonus]?
Final Damage = (((Base * (1 + .GunDamage)) * 1.15 CC) * (1 + .One Last Thing)? * (1 + .Load 'N' Splode + .Sapper COM + .Duality OZ Kit)?
The gear used:
LV50 DASTARDLY LONGARM
- Base Damage: 
LV50 SAPPER COM
- Explosive Damage: [+40%]
LV50 DUALITY OZ KIT
- Explosive Damage: [+50%]
Now I’ve tested both COM and OZ kit, the bonuses are not exactly +40 and +50% respectively, it is more like 39.5 and 49.5. For the sake of simplicity I’ve used only 1 stack of Load ‘N’ Splode because you can easily manage that 1 stack,
(3926 * 1.15) * (1 + 0.2 + 0.395 + 0.495) = 9436,141
So there is that, there are a couple of others thing you should know about Coincidental Combustion:
I would just like to add that for CC if you times the explosive damage boost by the chance of proccing the explosive damage you get an effective gun damage stat.
e.g. 5/5 points in CC: 0.35 * 115% = 40%
That is the base effective gun damage that this skill gives you, without including Load ‘N’ Splode stacks or other explosive damage boosts. Just goes to show how powerful this skill really is. With the right setup you can reliably get about a 90% effective gun damage boost at level 50, if you can combine Load ‘N’ Splode stacks x2 (pretty sustainable), Sapper COM and +50% from OZ Kit.
- CC doesn’t work with rocket launchers,
- CC can’t proc with explosive guns,
- CC doesn’t boost on critical hit,
- CC is not boosted by grenade damage bonuses,
- With multiple pellet guns, it gives boost only to single pellet.
Here is the info on One Last Thing and how it works with Coincidental Combustion.