Aquatic Respiration

Aquatic Respiration is the ability to breathe underwater. Users are usually not limited to how long they are able to stay underwater and some actually possess gills that allow them to extract oxygen from the water, thus, allowing them to breathe underwater.

Characters

 * Hulk

Hulk
The Hulk has been on the ocean floor a number of times. He is able to breathe due to his body developing a gland which creates an oxygenated perfluorocarbon emulsion which fills his lungs and equalizes the pressure. He is therefore able to breathe fluid and avoid decompression and nitrogen narcosis.