Cold Snap Witch - Advice Needed

Lots of good advice from people. I plan on compiling a lot of what people have said/what I've learned and make an actual build once I get to mid 70s. Right now I'm lvl 58, and people are loving having me in their merciless dock runs. I can easily keep the screen locked down, do decent damage and keep everyone safe.

Here's my big question right now; do I run Critical Weakness or Frostbite?

sorry i haven't been online for a while, (out of town)

to answer your questions

-my coldsnap has a crit chance of ~47% with 7 power charges.

-it is squishy in a sense that your only way to survive is hp pool, armor is virtually nonexistent due to voll's so you either have to find armor/es stuff with hp or armor stuff with hp and mp.

-and i use critical weakness with some quality. that is the reason how i can 1 shot white mobs. it is because of the +xx% more critical damage. and it also gives you a flat critical chance as well. currently my curse gives 8% so 47+8 = 55% crit chance with 7 charges. for groups i would say elemental weakness.

-as for how i got pass act3, i just ice speared everything. the mages that cast arc rip my face if my ice spear doesn't kill them off screen. the flag mobs in act3 are cold resist so it took a while but since ice spear crits all day everyday it didn't really matter.

Hey everyone, it's been a little while. Quick update time:

I'm level 67 now and am using Rime Gaze, two Divinarius, 5L Volls, Maligaros, and Sin Treks for my core items. Rime Gaze effectively gives me a 5L for my single target Cold Snap. I'm still looking into the best 5L combo I can do with it, but for now I'm running Added Cold, Added Lightning and Cold Pen. I know that's not optimal, but I'm still tinkering with it.

The two Divinarius give me ridiculous AOE which not only effects my AOE Cold Snap but also its Elemental Proliferation! An added benefit to this is that it also effects my Critical Weakness curse, which provides a huge boost to DPS and essential means I never run out of power charges.

Speaking of Power Charges, I have also been leveling a Discharge gem, and it's pretty damn fun. I never used it before, but I do think it is effected by Increased AOE passives/Divinarius because it's a huge explosion. As it levels more my plan is to alternate between AOE Cold Snap and Discharge to quickly wipe large groups. For blues and rares it still makes more sense to use the "single target" Cold Snap. My AOE increase is so large though that even my Concentrated Effect Cold Snap can still hit a number of mobs.

Last thing that I will talk about for now is that I barely have to use Ice Spear anymore. With Critical Weakness and two Cold Snaps I can almost always secure a crit off those.

Cheers everyone! Like I said once I get a little higher in levels and try maps ill write up a guide :)

*Edited some spelling,stupid iPhone.

I'm running an ice nova build atm but plan to switch to cold snap later on when I got 5l and some crit passives. My plan is to go elemental equilibrium with a totem spamming arc for shock which should help for the dps and 3 curses, temporal chains, elemental weakness and crit weakness, I think this should take care of the cc and dps, but still have to put it into action :)

One question about the penetration gems, if mob resistance to said element is 0 or below 0 there is no element penetration right?

Penetration cuts through a percentage of resistances above zero. I.e 20% pen on 50 resist would reduce their resist to 40. At zero or negative it would have no effect. At least from what I recall seeing.

Penetration can result in negative resistances.

http://en.pathofexilewiki.com/wiki/Penetration

Oh, awesome info about penetration! Thank you for the link!