note that helmets only prevent the doubled damage, not the automatic hit.
In AD&D, your critical miss penalty is up to your DM. For BGII, it just doubles the time it takes for you to make another attack.
In ALL of AD&D (2nd ed.) LOWER IS BETTER!! Saving throws, Thac0s, ACs, etc. should all be low. (note the obvious exception to the low-good rule is level...

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