I’ve seen people saying don’t put points into magic. Is this the same for Sorceress since she is magic heavy?

In the early game, we want to prioritize resistances, mana, and mana after each kill (mpk abbreviated from mana per kill). Fire and lightning resistances are the most important. Cold resistance is decently important too. And poison resistance is nice to have, but is not very important at all. Note that defense is nice to have when it sacrifices nothing else at all, but it is a stat that gives very little on your playthrough, so don’t worry about it much at all. Faster cast rate and plus to any relevant skills are very nice if you can get them as well, but they often don’t show up much till later in the game. And I also would prioritize mana over them, so that you aren’t constantly running out. Well you probably will be anyways, but mana and mpk help a lot.

(You can purchase a few socketed items in act 1, but don't use up many gems. If your drops are unlucky, you can get a +mana or two from gems)

After level 30 or so, and especially into Nightmare, we will shift our focus from mana and mpk to fcr and skills. The mana you get after each level up should be helping a bit at this point, and we’re just starting to need a little more fire power. In general, we’ll be shooting for 63+ faster cast rate (fcr), max (75) fire and lightning res, 55+ cold resist, and plus skills wherever you can get them. Either 20 or 30 faster hit recovery is optional but highly desirable if you can get it.

[I didn't want to type this out, since I learned it from this guy anyways! His guide is fantastic for sorcerer beginners!]

https://www.purediablo.com/strategy/diablo-2-sorceress-guide-blizzball-meteorb/

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