|This article is about a/an ally in Kamen Rider Blade.|
Trial B is an Electric-Type Undead disguised as Shiori's father, Yoshito Hirose. Originally, his program was to protect Shiori by her father because he was dying. Before he died, he transferred all his memories to the Trial. He is reprogrammed by Hiroshi Tennoji to continue to monitor the fixed Undead battle and remove potential threats. He dies saving Shiori from Trial G after remembering his original programming.
- Height: 218 cm
- Weight: 112 kg