Maybe they need to lay the wizard to rest? Seek an audience with the Goddess of Magic? Gather True Death in a sealed container by slaying the oldest lich in the world, to unleash it at the scarabbed place (or the workshop, possibly)? Find the ancient arch druid's notes on restoring Balance and follow the instructions left there? Reinstate the oracle priest to have him reveal the scarabs as an attempt by Mechanus to overrun the planes? Some combination of these and other suggestions and ideas?