Necro can get 9fpc and 40+ BS if DR is out of the way
10 P/B GC, 10x 17mana 5% frw sc.

2 skill 20% fcr ammy, 2 skill 20% fcr circlet, ViperMagi 30% fcr(1), lidless 20% fcr(1), 2 sojs, 20% fcr magefist/trang's. White wand 20% fcr (+3 bone, +3 BS), Trang's belt (50 mana CBF)
= 130 % fcr

Lv 44 BS, 9fpc, cannot be frozen and maybe lower mana.

Let's see...the necro's mana at level 99.

Necro starts with 25 mana.
Mana +2 per level
Each point in energy +2 mana
Base energy build.

25+ ((99-1)x2)
25+ (196) = 221

Lidless:
Increase Maximum Mana 10%
+10 To Energy = 20 mana.

2 sojs:
Increase Maximum Mana 50%
+40 To Mana

White Wand
+13 To Mana

10x 17 mana frw sc's
170 mana.

Mana from charms/items = 170+13+40+20 = 243.
243+221 = 464.
464 x 1.6% (increase max mana) = 742 Mana at level 99.

But the necro would have low resistance and no absorb, so the sorc could kill that necro in a quick orb'ing.