Sometimes simple character motivations are the best options to go with, because the reader/audience can easily keep track of it, it gives you a central point to base everything from, and it can create a clear goal for the character to strive towards.
Examples (spoilers for these shows/movies)
– Gravity Falls, Stanley Pines: To get his brother back
– The Martian,
Mark Watney: To get back to Earth
– Over the Garden Wall, Beatrice: To turn her family back into humans
– Roald Dahl’s The Witches, the witches: To get rid of all the children in the world
– Infinity War, everyone: To stop Thanos (an especially good one because everyone has the same goal, but different reasons for fighting him – e.g. revenge, to protect Earth, to protect a loved one, to stop him getting an infinity stone)
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