Based on their role:
* Catalyst: This character initiates the plot's central conflict or sets events in motion. They might not change drastically themselves, but their actions are crucial to the story's progression.
* Facilitator: This character provides opportunities or resources that help the protagonist achieve their goals. They might change in a supporting role, assisting the protagonist in their transformation.
Based on their change:
* Dynamic Character: This character undergoes significant internal change throughout the story. They are often deeply involved in the plot and experience personal growth or a shift in perspective.
* Developing Character: This character demonstrates gradual growth and development over the course of the story. Their change may be less dramatic than a dynamic character but still impactful to their role.
Combining roles and change:
* Supporting Protagonist: This character provides vital assistance to the main protagonist and also experiences their own journey of personal growth. They often play a key role in the plot's resolution.
Other terms:
* Mentor: A wise figure who guides and teaches the protagonist, potentially undergoing their own change through the process.
* Sidekick: A close companion who provides emotional support and practical help, often experiencing their own transformation alongside the protagonist.
Ultimately, the most appropriate term depends on the specific details of the character and their role in the story.