Splashdown consists of the following versions in Rhythm Heaven:
Unused Content
The Three Synchrettes have their full sprites included in their sprites, though their lower halves are almost always submerged underwater.
There are unused animations, such as "swimmer_show03" and "swimmer_show03_miss" being a fourth variant of the pose they use when resurfacing. There are also six test animations.
There is a function that sets how many swimmers are present onscreen. The only value ever used is 3, but 4 is also properly implemented. Values like 0 and negative numbers leave the swimmers underwater, and any other value places the swimmers in the middle over each other.
References