Aqua Kitty UDX originally started out as a puzzle-matching shooter

No matter how you slice it, Aqua Kitty UDX is one hell of a unique game. The game's official description describes the experience as "fast paced submarine action, defending the kittens from disruptive mechanical sea creatures." As out-there as the idea is, it seems the original plan was equally as original. Dugan Jackson of TikiPod Ltd. explains the game's initial design to NintendoPlay in the interview snippet below.

The original design was quite different, something more akin to a puzzle matching game involving shooting. We went through a range of experiments before ending up with gameplay we have now which is Defender-like. When we reached that point, we then turned to thinking how can we modernise that gameplay.So we made changes such as no longer needing to catch the falling abductees – adding weapon pickup systems – a secondary turbo fire gun which you need to learn to use in balance with the default submarine weapon – a selectable map allowing branching route choices (and the ability to retry levels at a whim) – varying sea level depths and so on.