Actually,an mf orb sorc is pretty easy
Skill placement as follows:
20 points ice bolt
20 points orb
20 points cold mastery
20 points telekinesis
1 point in all lightning or fire skills
and the rest of the skill points into energy shield
As far as stats go
str:enuff to wear chosen gear
dex:enuff to wear wizspike if needed(should be none really if u have torch and anni)
vitality:enuff to hit either 1000 life before bo or if you have a cta,enuff to hit 2k life after bo
energy:the rest,after all we use energy shield,right?
As far as equipment goes:
helmPtopaz shako
armorPtopaz skulders or ringmail enigma
shield:I find a spirit monarch helps survivability,but you could use an isted viscurtuant,or whatever else you might have
weapon:either an isted occy(ewh the tele when struck bites),or a dual isted alibaba(if your poor mf jewls are cheap enuff to use instead of ists)
rings:i find that a combo of 1 pnagel with a soj really works(if your rich a pwisp and soj works better)
amulet:tals ammy(or maras if your rich)
belt:tals belt w/as much mf as possible
glovesPerf chance guards(have an extra pair of tri-resist gloves for pesky monsters,lol)
Boots:wartravs of course
And in your inventory:
1 sorc torch
1 anni
1 good gheeds charm
enuff str/resist charms to put you at a safe range in hell
and of course a few good skill gc(cold gc's w/str are beautiful for an mf build)
With this build you can hit about 400% mf at lvl 88,and with a good merc that can do some elemental damage,you can mf the pit,andariel,mephisto,shenk,eldritch,thresh socket,pindle,and baal.Btw these are all in hell,not nm.
The damage i hit w/my orb on my ladder mf sorc with this build is 880-920 with occy and 720-810 with alibaba.This is enough damage to kill hell mephisto in 2-3 orbs,and most non unique hell monsters in just one orb(unless cold immune lol)