Flotsam oozes were medium-sized aquatic oozes. Their protoplasmic bodies were fully transparent, though may have been covered in debris thrown overboard a ship. They would, however, slowly digest any of the material that was organic.
These creatures were very good at concealing themselves. When creatures made contact with flotsam oozes, the oozes would release sticky substances that would stop the creatures in their tracks. The oozes would then follow up by repeatedly slamming them.
Even weapons would become stuck to the oozes, unless the attackers were quick enough, or strong enough, to release the grip. The sticky substance could be weakened by strong alkaline or soap.
In the 14th century DR, these aquatic oozes were known to lurk in the sewers of Waterdeep.