Ok here is an attempt at a spellcasting character.

Human
Lawful Good
Sorcerer
Str 13
Dex 13
Con 10
Wis 8
Int 13
Cha 17

Level Class/Feats/Attributes
1 Sorc(1) Power Attack, Combat Casting
2 Pal (1)
3 Sorc(2) Weapon Focus(any 1 handed)
4 Pal (2) Cha +1
5 Sorc(3)
6 Pal (3)Divine Shield
7 Sorc(4)
8 Sorc(5) Cha +1
9 Pal (4) Extra Turning
10 Sorc(6)
11 Sorc(7)
12 Sorc(8) Cha + 1 Empower Spell
13 Sorc(9)
14 Sorc(10)
15 Sorc(11) Still Spell
16 Sorc(12) Cha +1
17 Sorc(13)
18 Sorc(14) Spell Penetration
19 Sorc(15)
20 Sorc(16)Cha +1
21 Sorc(17) IMP. COmbat Casting
22 Sorc(18)
23 COT (1)
24 COT (2) Auto Still I, Dodge Cha +1
25 Sorc(19)
26 COT(3)
27 COT(4) Auto Still II, Mobility
28 Sorc(20) Cha +1
29 COT(5)
30 COT(6) Auto Still III, Spring Att.
31 Sorc(21)
32 Sorc(22) Cha +1
33 Sorc(23) Epic Warding, Greater Ruin
34 Sorc(24)
35 Sorc(25)
36 Sorc(26) Cha +1, Epic Mage Armor, Epic Spell Pen
37 Sorc(27)
38 Sorc(28)
39 Sorc(29) Great Cha I & II
40 COT (7) Cha +1

At 40th lvl your attribs should look like this.

Str 13
Dex 13
Con 10
Wis 8
Int 13
Cha 29

So AC without using your spells and only using base armour and tower shield with divine shield on should be

Base + Full Plate+ Tower Shield + Dex +Divine Shield
10+8+3+1+9= 31
With Epic Mage Armour. Empowered Eagle's Splendour and your other armour buffs you should be able to get this to a respectable 55+ with magical equipment even better.

With 29 Levels of Sorcerer and spell penetration the DC to resist the Sorcerers spells should be 29+6 for epic pene. +9 for Cha bonus(if I am right it counts to dc of spell) so a minimun of 45. not shabby at all.

With a large range of spells to throw and the ability to withstand a certain amount of punishment the battlemage can dish it out with the best of them.
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