Oh yea. Cleric/rangers are almost as good as they are in BG2, missing only on the fact that there is no dual wielding (the ranger dual wielding ability means that if they wield a single handed weapon and no shield they get an extra attack). I solo'd a C/R for a while, though it got tough and boring.
Just so you know, a paladin is VERY powerful in IWD, getting up to 6th level spells. I solo'd a paladin through the whole vanilla IWD and am currently starting on HoW. Between draw upon holy might (at high levels shooting your stats to 25-25-25), haste/RWotF, and Entropy Shield, you can have an untouchable mother of tanks that hits on NEGATIVE ROLLS

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