Certainly. There are a variety of well-regarded anime featuring themes such as the one you mentioned.

*Fullmetal Alchemist* and *Fullmetal Alchemist: Brotherhood* are dark fantasy sci-fi serieses focusing on a pair of brothers named Edward and Alphonse. It takes place in a world where alchemy is real and alchemists have magic-like abilities. It is know for its concept of "equivalent exchange," a notion that all gain requires equal sacrifice. While it does not feature any time travel that I'm aware of, it takes place in an alternate history that may be of interest.

*Steins;Gate* is another popular anime series, a science fiction story with more direct themes of time travel. It's about a scientist named Rintaro Okabe who accidentally discovers the means to send messages back in time.

*Attack on Titan* is another dark fantasy sci-fi series taking place in a world terrorized by gargantuan humanoid monsters known as titans. While the theme of time travel is not apparent through most of the show, it does play an important role later in the show's run.
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