Here's my first little islet for the Sea of Os'r project. It's called the Isle of Oxuders [PDF]:
At high tide, the Isle of the Oxuders appears to be two tiny islands.
The megalith is visible from a considerable distance to anyone keeping active watch. However, from the sea, it may be mistaken for a natural rock formation. The islands’s other points of interest are not evident unless the party makes a landing.There is a 2 in 6 chance the cast-away will spot the PC’s vessel, and ignite a signal fire on the highest point of the island, which otherwise appears uninhabited.
Boats landing on the beach at low tide must contend with oxuders, who often surprise by launching themselves from concealed burrows in the sand.