The amazon brigade that jumps you after you leave the Nashkel Mines. They're actually pretty easy to miss, since you need to head north to run into them - if you take any other direction, you'll never meet them, I think. I defeated them by dialing the difficulty down to Easy and chugging buff potions. On the plus side, they have really good gear for that level and give a good chunk of XP each.
As for Neera, sometimes the spells don't work right after casting the Reckless Dweomer even though they should. So I'll have her cast spells normally for now.