Q:I'm kind of new to this theory. I was reading the book and tried out the Demo program. I noticed that they mentioned eight archetypes. Are all of them present and needed for a story to be complete?
A: No, you do not need all eight archetypes for a complete story. In fact, you don't need ANY archetypes for a complete story. Characters are made up of character elements. Each element is an approach to finding and resolving problems. The eight character Archetypes in Dramatica each include a specific group of those character elements. Grouping character elements in any other arrangement creates Complex characters.
What IS important in your story is to explore the character elements--represented either by archetypes and/or complex characters.
In order for you to create a complete Grand Argument Story, all character elements should be explored. HOWEVER, some forms of storytelling, such as screenplays, have limited space and time with which to explore all the elements so a lot of shortcutting happens. That's why some people like to use archetypes--they're storytelling shorthand for groups of elements that might take much longer to explore individually.