The Protagonist

Characters - Main Cast

The leader of your story - if applicable. This is the POV character and as such should be one of - if not the - most complete character

Starting their Epic Journey

You'll wonder how to introduce your MC in an interesting way while also not slowing the story down. The first chapter is the key in getting this correctly, as it can make or break your protagonist and their involvement.
While the inciting incident doesn't have to happen in the first chapter, chances are you'll have to introduce their struggles and desires nonetheless - these help to understand the protagonist on a deeper level

On the other hand, once the journey actually starts, you will have to provide believable reasons for the MC to get involved in the main plot based on the established characterization you have given them. Remember that active characters are widely considered to be more compelling, so keep that in mind!

Mental characteristics

Personal history

The personal history of your character will determine every aspect of their being to the very core. Their flaws, virtues, desires and fears all stem from past experiences, especially childhood experiences

It is important to have a clear understanding of what happened to this character even before the story began. Chances are you won't get to introduce all of it into your story - and that's fine!

Education

Their education determines more than what you may think. The way they talk and the expressions they use are the easiest examples - but going a bit further, you'll see it influences their behavior, how they treat people and how they think of themselves. Their morals and values depend on this too

Writing side-characters?

Side-characters don't need nearly as much exposition as the main protagonist, even if the protagonism is shared on some level. If you're writing a character that will have a mostly passive role in the story, but that has some agency nonetheless, consider expanding only on these items:

Role in the story, as in, 'support', 'powerhouse', 'parent', etc
Personality: How deep you dive into this one is up to you - deuteragonists will need just as much personality as the protagonist, but background characters can have a few defining traits
Background: Only the bits your audience needs to understand their motivations

Conditions

Flaw

Children

Related Myths

The Hero's Journey

Ask yourself...

Why is the protagonist launched into action?
Do they have a choice in that matter?
How are they going to achieve their objective, whatever that may be?

Motivations

Crafting a believable motivation is key to getting the reader invested in the story. This could be achieved by linking it to personal motives and desires, but they could also be forced to take action by forces outside of their control

What about short stories?

While you won't be able to develop your MC as much, their goals and motivations should still be clear

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