Level 77 Crit Winter Orb Elementalist^3.26

Notes

===== PLEASE READ ATTENTIVE =====
1. I don't recommend starting with Winter Orb right away. The earliest you should, is at Lv 38 when you have access to GMP, but you'll lack damage. 
2. Start with something else (like Creeping Frost) to get you through campaign and early maps.
3. You can transition into Winter Orb in your mid 70's as you really want them skill points. That's why the first passive tree is set for Lv 77.
4. The other two trees are for further levels - and this is just to give an idea of where to go and depends on what you prefer:
  4.1 You can either go more offensive with power charges. This way you can replace increased critical strikes for anything else like infused channeling, increased area of effect or power charge on crit (and respec the caster mastery)...
  4.2 ...Or go more defensively with life/ES nodes, reduced crits taken and capping your spell block chance.
5. You basically can switch the 50% auras to whatever you like. If you want more speed, use (Vaal) Haste. If you want more defence, use (Vaal) Grace (this of course also depends on the merc you have but I didn't take Mercs into account for this).

Gear:
- See Uniques listed under 'Items'
- For a pseudo 5-link, you can use Calisa's Grace (gloves) (if lucky corrupted with flat spell crit or a curse) and an Obliteration (wand) if you don't have anything better when transitioning.
- Before you use Carcass Jack, you can allocate the life mastery for 15% increased maximum life if you don't have any life mods on your body armour.
- Anathema is a good QoL but you don't need one right away. Until you have one, only run one curse/mark and Vortex + Frost Bomb (it's only for single targets anyways). 
- Helmet, Gloves, Boots: look for Eva/ES bases with life and resistances/attributes. 
- Rings: life, resistances, attributes, cast speed (craft -mana cost if needed)
- Amulet: +1 to cold or all skills, alternatively The Pandemonius. Cheap anoint options: Amplify (AoE), Harrier (movement, cast speed), Nimbleness (cast speed, crit multi), Storm Weaver (damage), Holy Dominion (damage, ele res)
- Shield: alternatively to Zeel's Amplifier you can also get a rare one with +1 to cold spells and damage mods or get block chance and spell block chance capped and safe some points (you could also consider swapping shields for mapping and bosses).
- Capping resistances and getting the needed attributes should be relatively easy with Alira + Purity of Elements
- Get Bleed/CB immunity on your life flask asap
- Try to get a source of life leech on your gear. Your best bet is either a helmet/amulet corruption, eldritch implicit on gloves or use a Berek's Grip.

Ascendancy/Skill Tree: 
- Elementalist: Golems first. After the 2nd lab, I'd take Shaper of Flames for more defence. After 3rd lab respec Shaper of Flames and get Mastermind of Discord (make sure you have the cold mastery for exposure) and Heart of Destruction.
- If you want faster clear with explosions, you alternatively could also choose Occultist (get a Mark of Submission) and respec later. Order: Profane Bloom > Void Beacon > Forbidden Power or Frigid Wake
- If you want to go more safely in uber lab, you can respec again and use Shaper of Flames + Bastion of Elements or Shaper of Winter.
- You can also take the res-inversion ele mastery (only do this if you don't have any sources of res-lowering/pen).
- For ele reflect maps you can take Yugul + ele mastery.
- You can also take jewel slots if you got any good ones.

Pantheon:
Brine King (for stuns) + Shakari (if you don't run Purity of Elements, take Abberath and change charge mastery to 'cannot be shocked').

Skill Gems:
- Don't run RF until you're low-life/ES because this will give you a huge recovery degen.
- You can also run defensive curses (Temporal Chains/Enfeeble) in the Arcanist Brand setup (with Anathema)
- If your strength is high enough, run Automation + Steelskin instead of CWDT + Immortal Call
- The links and colours on your gear are flexible. You only want Winter Orb in your weapon and Arcanist Brand in your body armour. The rest can be socketed as you like. You can for example also run Vaal Lightning Trap instead of Shield Charge for a safe 15% shock or link Culling Strike to Flame Dash.
- Don't forget to level some needed gems for later in your 2nd weapon set

Requirements for transitioning into low-life/ES: 
Make sure you have the following items before following the main PoB:
- 6-link Shavronne's Wrappings (body)
- Mystic Refractor with 3 projectiles (wand) 
- Anathema (ring)
- Prism Guardian (shield)
- Decent ES gear
- Belt: you can keep Immortal Flesh for a huge regen boost or slap on a super cheap Bated Breath to start with