Things look pretty grim, unless. . .
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along with the obvious tactic of removing Belkar's curse, they find that bone fragment that was rattling around in Roy's boot and use it for the Resurrection scroll--which would bring Roy back immediately at full hit points (though at -1 level from when he died). Roy, Belkar, and Haley along with some sylph lightning from Celia and whatever support magic the cleric can provide should make short work of the three rogues seen above, unless they get reinforcements.