The characters made their way deeper into the forge complex, encountering mechanical golems that were clearly jury-rigged to be barely functional. They also encountered the ghost of the artificer Hestius who had built the forge.
Hestius warned the party that they would never reach the forge. Even if they did, he said, Calamachia would stop them. Hestius left them, but released a bone wyrm and swarms of tomb mites to harass the characters.
After defeating the undead, the characters, weary and wounded, trudged onward into the forge complex.