During Power Ranger in Space, Astronema created the Psycho Rangers to drain the power of Dark Specter so she could take over as monarch of evil. Each Psycho Ranger was obsessed with defeating the Ranger of their colour and each used a weapon similar to their Ranger. They were defeated but later came back with the use of a digitizer and were digitized into cards at the end of that episode. They would again return in Power Rangers Lost Galaxy as the reason for the first ranger team crossover episode.
Psycho Blue uses an axe and was an ice like monster in his true form.
Other Media
Video Games
Power Rangers: Legacy Wars (2017)

Psycho Blue appears as a premium recolour skin for Psycho Green.
Merchandise
Psycho Blue has been around since 1998 (1997 if you consider his Super-Sentai counterpart) and owned by Saban Entertainment. During that time, the merchandising was handled by Bandai, with Psycho Blue only receiving the toy treatment in 2018 for the first time before the rights were bought by Hasbro.
Toys

- Psycho Blue is part of the sixth and final wave of Bandai’s Power Rangers Legacy Collection released in 2018. His psycho axe can be equipped.
- Psycho Blue is also part of Hasbro’s Power Rangers Lightning Collection released in September 2019 and is a GameStop exclusive action figure.