The Iron Mage

Demigus, Splinters & Yar agree to help Hiro retrieve a strange iron ship from the world's edge. Keraptis, a mad wizard, plagued the seas with a fleet of strange iron ships hundreds of years ago. Hiro has discovered Keraptis lair, a volcanic island of the eastern coast of the Isle of Bones, and employs Wulgar, captain of the Winter Dragon, to provide transport. The voyage to the Isle of Bones takes a week on the Winter Dragon. During the journey, the crew rescue a strange castaway sacrificed to Tiamat and cast adrift on the ocean at the edge of the world.
The Island of the mad mage is an almost perfectly conical volcano formed from slow lava leakage. It rises about 800ft above the sea. From the summit, a continuous geyser trails in the wind like a tremendous white feather. The spray collects into depressions downslope and merges into a sizable stream. On the eastern face of the Island is the Wizards Mouth, a vast sea cave large enough to for two longships to sail into side by side. The Wizards Mouth seems to exhale a large steam cloud then slowly inhales it like a person breathing on a cold day. Each cycle takes about 30 seconds. A massive iron portcullis bars the Wizards Mouth. The adventurers climb several hundred feet up the cliffs to the service tunnels to open the portcullis. But the door to the service tunnels is wizard locked. One of Keraptis's pets, Erasmus, offers help if the adventurers set him free and challenge them with three riddles. The party answers Erasmus riddles swiftly to his delight, giving them the key to the door. From there, adventurers fight there way through ghoul infested tunnels to the control room, using hydraulic gadgets to open the portcullis and gain access to the inner harbour.
The inner harbour is a vast sea cave, and warm air from geysers circulates in a steady breeze through the Wizards Mouth. To the west of the cave lies a broad sandy beach. The remains of ship hulls jut from the sand like the rib cages of rotting corpses, and a strange vessel that looks more like a keep than a ship bobs against a floating pontoon. East of the beach, dwellings, and walkways are carved into the rock wall, in a bewildering array of staircases and slopes. Erasmus was not what he seemed; he is a manticore, a terrible monster with a taste for flesh who wants to eat the entire crew of the Dragon. Too large to fit in the service tunnels, Erasmus had tricked the adventurers into opening the Seagates. A deadly battle in the ruins of an amphitheater ensues. Hiro, Wulgar, Demigus, Splinters, Yar, and berserkers from the Winter Dragon slay Erasmus. Hiro and his clan claim the last of the strange iron ships as home, and the Winter Dragon sails back to Three Towers. 

In the ruins of the cliff face town is another huge bust carved out of rock.  A huge wizard's head, the mouth of which bellows clouds of steam, much like the great sea gate.  
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