We meet many characters throughout the game; some are heroes, some are not, but every character has a purpose, even if it's only to give us one quest before moving on.
Heroes are characters that you rescue from crystal prisons, and who can then go on adventures for you in various Places of Legend.
Other characters are, well, the other, non-hero characters. They may be there throughout the game, like Myra and Glurb, or they may come and go after only one meeting, like the Knight who gives us the Admirable Alliances quest.
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