If you loved Code Geass: Lelouch of the Rebellion III - Glorification, try Code Geass: Lelouch of the Rebellion I - Initiation
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
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Code Geass: Lelouch of the Rebellion III - Glorification
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Code Geass: Lelouch of the Rebellion I - Initiation
What they share
Both films are directed by Goro Taniguchi, and they sit in Action / Animation / Drama / Science Fiction territory. If that's the register that drew you to Code Geass: Lelouch of the Rebellion III - Glorification, the second film will land in a comparable space — through a different lens.
What Code Geass: Lelouch of the Rebellion I - Initiation is
You fight in a war-torn world, but then a mysterious girl grants you a powerful ability, and the director sets this story in an alternate timeline.