Fascinating story, @ipexito. It made me go look up promethium!

A radioactive metal. Most promethium is used only in research. A little promethium is used in specialised atomic batteries. These are roughly the size of a drawing pin and are used for pacemakers, guided missiles and radios.

Promethium is not found in the Earth's crust. However, it can be observed in uranium ores as a product of uranium decay. In addition, it can be found in the Andromeda galaxy.

The bamboo forest transforming into a monster was inspired. Poor Philip. It does not seem he will be making it back home to his family.