Crystal Caverns is a Hard Map made by FloodEscaper1. It has 7 Buttons and 1 Group Button.
As stated in the title, the map has many crystals throughout the whole map. When getting the second and third buttons, a sound of glass breaking is heard. Going underwater, a significant number of crystals is present, proving an obstacle to players swimming. As the map states, there are many crystals placed on the map. The texture of the platforms is a similar color, pale and white. A sound of glass breaking is played when pressing the first three buttons. In the first underwater section, the crystals form the major obstacle. Later on is a much bigger underwater section, where you go under tunnel-like areas and finally swim upwards, press the last button, and swim to victory.
Experienced players can preemptively wait at each button for a faster time.
FloodEscaper1 has made a few other popular maps in FE2 Map Test.
This is the only map where water doesn't change into acid or lava.
Many players say that this is a boring map due to the same color theme of the map, mostly swimming in the map, and weaker and slow beats of the song.