Lagoon is a music track that is unlocked on Fossil Island when diving underwater.
This track has a varying tempo (it increases and decreases), but it stays close to or around 90. It is in the key of E Major, which is a generally happy key that represents delight and joy.
It starts out with the Seashore sound effect instrument, then it goes into a beautiful harp section accompanied by a Warm Pad and Slow String instruments. Further into the song it dips down even deeper in the melody to give the feeling of being deeper in the ocean. But then it rises back up suddenly to repeat the melody. As the song goes on, more accompaniment is added subtly, such as a choir or vocal instrument along with the drums which are extremely quiet and serve as backing tracks. The song slows down towards the end and comes to a complete stop.
- This song's tempo and melody varies in which the song forms slow "musical waves", most likely to represent the situation of being in the ocean.
- This track seems to be a rearrangement of a previously made track called Lullaby. Lullaby is in the key of E Major as well but has a constant tempo of 90.