Arc

OMG, this skill makes me wanna roll a Lightning Witch so much!!! :3

Finally we see some love for the Lightning-side of the equation.

Lighting/summoner witch lvl 70 -

My thoughts

1. Mana cost far exceeds usefulness/dps.
3. Poor synergy with support gems
4. Low crit chance

Pros.
1.Looks cool

I'll reserve my other thoughts until its fully leveled.

I rolled a Lightning Witch just because of this skill. I planned her out so that Arc would be her main spell to spam, but in reality Spark's going to end up being a much better skill for me. It's sad 'cause I really like the look of Arc and chain lightning spells in general. :(

I personally don't find the mana cost to be a bother even this being my main spam skill, with my witch's build I have no mana problems unless I spam my totem but thats why I have a mana flask that has 100% effect on low life so my mana is always topped off. I am rolling a pain attunement build and I must say the dps is rather nice, I just drop my totem and hold shift+left click till mobs are dead.

No mana problems either , i use clarity and dream fragments and because i use CI i can have 3 mana flasks and 2 granite just in case. Imo the fact that its dmg aint as high as Ligthning Arrow is not a problem , im focusing more on a shock effect - Arc has 10% chance , shadow has passive for +5% chance , and there are 2 more passives next to Minion Instability for 20% chance that gives you 35% chance to shock on hit , use Conductivity on top of that and you got 45% chance to shock + your crit chance ofc. Elemental Proliferation spreading that and you have whole group shocked with 3 stacks after 1-2 Arcs.

ya i put it on my totem and love it, im a crit marauder BM caster and have a crit damg. gem with it and iron will and it works great. pluse i spam chain LMP ice spear too so im one deadly waking pinball machine.

fresh lvl 25 sparc witch (calling dibs on "sparc") using spark + arc

i find the dmg being too low for nontargeted spell,sometimes its really hard to hit priority targets (necromancers,snakes,vaal peashooters),i have to clean everything in front of them before i can start killing them - so when i cannot one shot nor slow/freeze mobs like ice witch the battle looks like me running back all the time spamming arc

in close encounters spark is still better spell to use

id rather see arc being more chains,same dmg or 1 chain more dmg because of no CC the dmg has to be significantly higher

well see what happens when i pick double totems,hopefuly this build will start shining

I just converted my lvl 27 cold witch to lightning to try this out. Very underwhelming, unfortunately. I'm currently using lvl 1 Arc, along with lvl 5 Added Lightning and lvl 2 Increased Crit Damage.

I do love the auto-targeting, but I haven't gotten into too many situations where I really need to target a specific mob first (necros come to mind). I think that the mana cost is definitely too high for the DPS I'm getting out of it. Compared to ice spear, it's almost useless at killing big targets. DPS is 59.1 for 30 mana. I drain 2 mana flasks just trying to kill one rare mob.

I was hoping this might have the single-target punch to make it a good main skill for a lightning witch, but it seems to be more in line with Spark, which is spread out damage on top of being unpredictable in power. I'd rather see the power increased and mana left the same, but something needs to change I think. Guess I'll be sticking with Spark for now. Don't think I'll survive with Arc. Can post my build or equipment if needed.

Arc totem needs a slight fix.

This combination results in arc firing from the totem's base instead of from the totem's tip. It's a small change but it will make a big difference to how the skill combination feels. It doesn't feel quite right as it currently is.

I wanna love this skill, I really do... but I can't, not until they buff it.

And I use Cold Snap, so you know I'm all about the underdogs. I can honestly say Arc needs a buff. I still have to level it some more, but I changed all my passives to lightning nodes, with 0 buffs for cold damage, and even then, freezing pulse comes out on top.

So, what is the main problem for me? Its mana cost is too high, specially when you try to support the skill. The cost skyrockets.

I can't really talk about damage until I level the gem further. Maybe they could reduce the cast time to 0.7 as a compromise?

Regarding its chaining properties, the skill certainly would be more fun if it added a couple more targets in the long run, but it's not a deal breaker if it doesn't.

my $0.02