Around about level 16. I'm playing a human Ranger, and I've got Aerie, Jaheira, Minsc, Imoen, and Har'Daelis. Highest level spells any of them have is 7th...and I've not many of those. Didn't really like most of the spells I found through the quests and in stores.
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Playing the cutest li'l Chaotic characters since 1996.