The Keep of Dragon Turtle Greth

An entry in the Tenfootpole Waverider Keep contest! From the publishers blurb: Fear the tides! For upon the ocean’s black abyss rides a keep of stone on the broad shelled back of the mighty dragon turtle Greth. Fear the tides! For unbeknownst to the fisher families of Stonewave the tides have turned against them. Fear the tides! For this night, the vast body of Greth will beach itself upon the shore and a score of Iguanamen will be disgorged to raid the town for fresh human flesh. Can the party fight off the Iguanamen raid in the night? Can the party reach Greth in time to rescue the captives before he dives into the deep?