The Sorceress has three categories of elemental skills which they may use: cold, fire, and lightning. This gives rise to the three key types of sorcs: Fire Sorc, Cold Sorc, and Lightning Sorc.
Each category of sorc can generate massive amounts of damage to inflict upon the beasties of the game. That is the good news. The fly in the ointment is that many monsters have resistances to the various types of elemental damage. So if a monster has as 50% resistance to fire and you are playing a fire sorc, then you will not be dealing as much damage as you'd like. That is the fly in the ointment. Now for the really, bad news: when you get into nightmare and hell levels of the game, almost all monsters have one type of immunity or another.
Thus, in hell mode (and even nightmare and yes even parts of normal) monsters might not be effected by a sorcs spell at all -- that means zero damage. Your lighting sorc might be capabile of doing 10,000 points of damage, but, to a lightning immune creature it is not even a tickle. They are completely 100% uneffected.
If you want to play and contribute in hell levels of the game, you need the massive damage of a focused sorc. But if you focus on one of the elemental types of damage, you can do zero damage to a creature immune to that flavor of element. This means traveling in a party (always recommended) so that others may take up the slack in those situations in which your character is helpless. Or, this means running away from those situations in which your character is totally ineffectual.
I happen to like the lightning sorc. The combination of graphics, sound, and effectiveness in game play make this my preferred type of sorc.
The two key skills to a lightning sorc are "Chain Lightning" and "Lightning." The chain lightning is great for groups of monsters. It does less damage per hit, but it does many hits. The lightning is great for single monsters. It does only on hit, but it does more damage. And when fighting a single creature the chain lightning will only hit once. So lightning for head to head battles and chain lightning for groups.
Charged Bolt, Nova, Lightning, Chain Lightning, and Lightning Mastery. These are the big five. They work synergistically such that points added to Lighning not only enhances the damage of lightning it also enhances the damage of chain lightning -- visa versa and et cetera.
If you look at the screen shot you will notice that Nova has only 9 skill points assigned to it. If this is a synergy for lightning and chain lightning why have we not assigned more points to it. Even though we don't use nova it will still add good damage to the other key skills. Well, the answer is simple: there are not enough points to fill all of the synergies.
The sample character we use in these examples is at level 85. If you take a character to level 99 you would have enough points to complete filling nova. But, don't even think of taking a character to level 99. That is plain stupid. It will take you night and day for a year to get a character to 99. There are better things to do within the game than concentrate on a single character.
One point in Frozen Armor is enough when supplimented with skill points coming from your equipment. By the time your character reaches level 85 and is banging around in hell the equipment should be giving somewhere between +5 and +9 skill points.
One point is put into the skill "Warmth." This will increase the rate at which your mana will recover. Since the sorc uses a tremendous amount of mana to work her spells, you need mana replacement. A sorc does not "hit," so mana steal will not come into play. Hence mana regeneration, and drinking mana potions are the two key mechanism for mana replacement.