Code Geass: Lelouch of the Rebellion R2

You may know this one as Code Geass: Hangyaku no Lelouch R2; that's Code Geass: Lelouch of the Rebellion R2 under its other release name. Sunrise produced this TV series across 25 episodes. The run is complete — no gaps waiting on new episodes.

Genre-wise it's tagged Action, Drama, and Mecha, which is the throughline if you're browsing by mood rather than by name. If Code Geass: Lelouch of the Rebellion R2 works for you, Attack on Titan and Demon Slayer: Kimetsu no Yaiba are close matches — see the full related list below.