If you can't resurrect, you probably have an Elven thief. I played my first time through with an Elven Mage -- talk about reload

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If you are particularly fond of that thief, use Gatekeeper. You might be able to just take a saved game and reset hit points without having to recreate a character. Otherwise, get ready to level up a first level thief.
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Most Subtle Official Straightman of the Laughing Hyenas -- Grammarian Brigade.