The skill distribution with this build concentrates on maximizing the harm output of Firewall and Frozen Orb, in addition to synergies and utility skills. Something to notice here is that given Firewall's insufficient effective synergies (warmth being decent, and inferno being a weak synergize (+1% damage), it's unnecessary to get more than around 60 points in Firewall, Synergies, and Fire Mastery. Frozen orb is comparable, with just one synergy and mastery which makes it a great secondary damage and cc spell.
Fire Bolt (1 point): Pre-requisite
Fireball (1 point): Pre-requisite
Firewall (20 points): Primary fire damage spell.
Warmth (10+ points): Mana regeneration skill along with a new synergy to Firewall in D2R (+4%)
Inferno (1 point): weak synergy to Firewall (+1%)
Ice Bolt (1+ point): Pre-requisite and synergy
Ice Blast (1 point): Pre-requisite
Frost Nova (1 point): Pre-requisite
Glacial Spike (1 point): Pre-requisite
Blizzard (1 point): Pre-requisite
Frozen Orb (20 points): Primary cold damage spell.
Cold Mastery (10+ points): Increases cold damage by lowering enemy resistances. This caps out at -150 resistances, so don’t skill the power past this.
Static Field (1 point): A must-have for those sorceresses, reducing enemy health with a percentage.
Telekinesis (1 point): Pre-requisite for Teleport.
Teleport (1 point): A vital mobility skill.
The remaining skill points can be put into Fire Mastery to help boost Firewall's damage or Ice Bolt for further Frozen Orb damage.
Strength: Enough to equip gear (typically around 110 to 120).
Dexterity: Enough for an optimum block, if utilizing a shield like Stormshield, otherwise leave robust.
Vitality: All remaining points.
Energy: Base, as the gear usually supplies sufficient mana.
Harlequin Crest (Shako) socketed by having an Um rune or perhaps a 5/5 Fire Facet.
Crown of Ages is a Hardcore optioning offering superior survivability at the cost of strength investment
2/20FCR circlet to achieve higher teleport FCR (note most of your abilities have spell cast delay)
Chains of Honor (Dusk Shroud or Archon Plate base). Enigma can also be viable and saves teleport skill points. Vipermagi or Ormus could be viable if FCR is chosen.
Heart from the Oak (Flail base) for +3 all skills, resistances, and 40FCR. Eschutas, Occulus, or Death’s Fathom could be viable but don't have the well-roundedness of Hoto.
Weapon 2: 'Call to Arms' runeword inside a Flail or Crystal Sword for that pre-buff.
Shield 1: Spirit Monarch for FCR, mana, and resistances.
Shield 2: Spirit Monarch for pre-buff.
Gloves: Magefist for FCR and mana regeneration. Or Trangoul’s should you prefer Cold res.
Belt: Arachnid Mesh for FCR and skill bonuses.
Boots: Sandstorm Trek, War Traveler, or Waterwalk for any mix of stats and survivability.
Amulet: Mara's Kaleidoscope for +2 to any or all skills and resistances.
Rings: Stone of Jordan for +1 to any or all skills and mana, along with a Bul-Kathos Wedding Band or perhaps a rare/crafted ring with FCR, resistances, and life/mana.
Charms: Your standard anni/torch and fire skillers should be from the majority of your inventory. If you require any FHR hitting your desired breakpoints, consider purchasing small charms. Otherwise, concentrate on finding life and fire resistance charms to counterbalance the Fire Sunder you ought to be using. Do not use cold too unless you're sure you can survive. It is very hard to try and offset -100 resistances in addition to an additional -140 from 2x Sunder Charms.
MF Alternative build
If you're opting into an MF build, here are a few item choices you can consider. Remember, that you are simply a hybrid, as well as your damage sources, happen to be suboptimal. Be careful that you simply don’t sacrifice an excessive amount of damage for MF in the event you become less efficient.
Helm: Shako (Ist rune)
Armor: Enigma (Huge str and MF boost)
Weapon: Oculus with Ist
Shield: Spirit Monarch
Belt: Goldwrap (upgraded for added potion slots)
Boots: War Travellers
Amulet: 2/10/MF Amulet
Rings: FCR rings with life, mana, and resistances and MF, or Nagelrings, or magic rings with +40%MF
Act 2 Mercenary:
The Act 2 Nightmare Defensive (Holy Freeze) or Offensive (Might) Mercenary is the best option for this build. The Holy Freeze aura aids in crowd control, as the Might aura increases your mercenary's damage output. Given you have Frozen Orb, it's recommended you opt into Might. Prayer may also be useful even though life regen is minor.
Weapon: Infinity runeword within an ethereal Thresher or Giant Thresher for that Conviction aura, which lowers enemy resistances, greatly enhancing your elemental damage for both damage sources.
Helm: Andariel's Visage (socketed having a Ral rune or 15% IAS jewel) for a lifetime steal, increased attack speed, and +2 to any or all skills. 15ias jewel is required to hit the maximum attack speed breakpoint when wielding a thresher.
Armor: Fortitude runeword within an ethereal elite armor for enhanced damage, resistance, and life.
If Infinity isn't attainable because of its high rune cost, think about using Insight for that Meditation aura, which aids in mana regeneration, or Obedience for high damage and resistances.
Playstyle and Tips:
Start by casting Frozen Orb from a safe distance to slow and damage categories of enemies.
Cast Firewall under slowed or stationary enemies for massive fire damage.
Use Static Field on high-health enemies, especially bosses, to lower their health quickly.
Teleport around the battlefield to keep a safe distance and position yourself strategically.
Make sure to keep your Battle Command and Battle Orders buffs from 'Call to Arms.'
Switch for your secondary weapon setup to pre-buff your talent and cast your buffs before switching back to most of your setup.
Keep your mercenary alive, as his Conviction aura in the Infinity weapon greatly enhances your damage output.
Use full rejuvenation potions you discover along the way, you should also repair your gear regularly.
This Firewall / Frozen Orb Hybrid Sorceress build supplies a versatile and powerful playstyle, ideal for both PvM and PvP. It’s fun, unique, and visually stimulating while being quite effective. Your spells have cast delay do require serious amounts of getting used to, but together give a good layering of dual sourced elemental damage.