|Manga Debut||Chapter 267|
|Anime Debut||Episode 196|
The Rain Shonisaurus is a Rain-attribute Box Weapon that merges the body of its user with the power of the Shonisaurus through the use of a Box of Carnage. The Shonisaurus specimen that served as a base was a dinosaur with a body length surpassing 20 meters that lived approximately 200,000,000 years ago. Bluebell's appearance in this state resembles that of a mermaid.
Through this Box of Carnage, Bluebell gains superhuman cardio-pulmonary capacity, diving abilities, and the ability to envelop her body in an impregnable barrier. As a result, she is unbeatable in battles underwater. She can also float around without using Flame Boots.
- Bomba Ammonite: Bluebell creates a shell covered in Rain Flames and launches it at her opponent.
- Barriera Medusa: Bluebell creates a field of transparent, completely pure Rain Flames around her body. This pool of high-purity Flames can make the movement of molecules come to a near halt with their Tranquility factor. In order to draw enemies into this field, Bluebell purposely puts up a flashy protection around its limits.