The Laboratory is the second area accessible within the Lunar Soul Castle. Its theme is "Geothermal".
This area is mostly purple in color, and appears to be in ruins. There are two exits. Laboratory E goes to the Entrance, while Laboratory R goes to the Reservoir. The Warp Doors can be found at Laboratory SP.
- Crescent Moon: obtained at Laboratory O.
- Life Capsules: these only appear outside of 3-HP mode. In 3-HP mode, they don't appear at all.
- One is found at Laboratory E. The status bar might conceal it. It increases HP by 3.
- One is found at Laboratory V, and increases HP by 5.
- One is found at Laboratory I, and increases HP by 4. It is possible to obtain this Life Capsule without having the Valkyrie Wings.
- One is found at Laboratory C, increasing maximum HP by 1.
- Chocolate Cake: obtained at Laboratory C.
- Sycor (major boss)