Stormfire - which is a cool item skill you get from Seal of Destruction could use a buff. I just had the opportunity to use it as a filler between cooldowns after all the time i put into Grim Dawn, and i noticed, it is really weak compared to Chain Lightning for instance. (Chain Lightning deals about twice damage on an equally optimized character, both using daggers)
It may not be very important as the skill will probably never meant to be any significant damage source, but numbers still look really weak even as a filler skill.
EDIT : For reference, my fully min maxed fire blightlord oppressor has 10-14k Stormfire sheet damage. You can of course push this damage more on certain builds, but it’s still a negligible damage.
Do you think it can every hit one (maybe big-ass) enemy multiple times? It doesn’t look like that but I don’t know.
(I looked at the video but don’t want to stare at it too much as I don’t have the best eyesight.)
Anyway, it’s certainly good for groups of enemies. But it’s weaker than Chain Lightning / Chillspikes on a dummy according to my limited testing. I check it out a few days ago with a character having about 90% Elemental -> Physical and no Pierce conversion
and Chillspikes / Chain Lightning were about equal and Stormfire was far behind. Bug again, it was only single target test.
I dont doubt its better or worse in situational cases. In the case of that infiltrator i tried chain lightning too. Stormfire fully converted and kept me alive better when facetanking 4 nems while with chain lightning i found myself dying more often.
Stormfire used to be pretty broken back when Cyclone was top tier. It’s still ok, though. However, I’d up the % wpn dmg so that it leeches better. Maybe at the cost of flat dmg. I feel that nerf was too harsh, especially accompanied by all the generic nerfs of lightning dmg.
: so what you’re saying is, Chain Lightning needs a nerf ? 
