Underwater Skeletons are speculated to exist in GTA Vice City. These skeletons are rumored to be found in the shallow waters of Vice City, similar to the Cement Shoe Men. The other similarities include the cement shoes fitted with the skeletons.
This myth is basically a result of the fan fiction originated from the Cement Shoe Men. Players wanted to explore more about the Cement Shoe Men, came up with the idea of cement shoe skeletons, and speculated that the human form could've disappeared over the time and the skeletons could be placed in the olden days.
Videos have been developed in this regard, featuring these skeletons. These videos were made by 3D modeling, texturing, rigging and animating the skeleton on the bottom of the ocean. However, due to the lack of any physical evidence excluding speculations and modded features, the myth is rated as false and a result of modifications in the game.