recently I tried soloing a beastmaster at suicide difficulty! It was going pretty well until...
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I got to the last area in Irenicus' dungeon level 1 where you have to open a trapped chest to get a portal key. Since I had no thieving skills, I couldn't detect traps nor disarm them. I sent my familiar to open it and the first trap killed him, but I always died on the second one.

Haha! That is exactly what I'm doing with my Drow Fighter, except I'm in BG1. Setting the difficulty to maximum is very challenging. I'm level 5 now, and Mustard Jellies are still able to kill me! Even when I have an AC of -5! On the matter, there was someone who played through the game with a Beast Master and found the benefits of it, I'll try to find the archive.