One feature of an underwater is caustics, when light pass through the water the light bends and creates caustic patterns or refractions on the water bed. Best way to simulate caustics as efficiently as possible is to fake it using textures.
all the textures are done procedurally in maya. No unique shaders or any complex tools used.
HCA ImpressMiss (Test)
Fix: Distorted Motion Blur / utensils shaders & texture/ subsurface clothes / flickerings/ fog/ light artifacts/ lighting
