If you loved Atlantis: Milo's Return, try Buzz Lightyear of Star Command: The Adventure Begins
A bridge between a film you've already seen and one most people haven't. Buzz Lightyear of Star Command: The Adventure Begins has roughly 11.8× fewer votes than Atlantis: Milo's Return — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.
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Atlantis: Milo's Return
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Buzz Lightyear of Star Command: The Adventure Begins
What they share
Both films are directed by Tad Stones, and they both carry the playful mood tag, and they sit in Action / Animation / Family / Science Fiction territory. If that's the register that drew you to Atlantis: Milo's Return, the second film will land in a comparable space — through a different lens.
playful
What Buzz Lightyear of Star Command: The Adventure Begins is
Buzz Lightyear apparently needs backup. He battles Emperor Zurg with three wannabe partners. It manages to launch a franchise.