Attack on Titan is an intricately crafted anime with a well-developed world setting. The anime traces back to the Titans' birth and the upcoming wars with igniting conflicts, rivalries, and hatred among different races, nations, and human beings. Each nation possesses a unique worldview, social structure, and physical environment to safeguard themselves. The hometown of the protagonist Eren is a classic example, with three daunting walls and the exhilarating three military branches to maintain the country. With the world setting, numerous main and supporting characters embark on difficult journeys, seek the meaning of life and exploring their true selves.

Despite the abundance of characters, almost every major role is depicted with profound depth and uniqueness. Even those who are not the main characters possess astonishing character development. The richness and subtlety of these characters do make the anime quite lengthy, but they also make the fictional world real.

The inter-human warfare is the main setting, but the anime delves into deeper themes, such as human vulnerability, fear, selfishness, and growth. Some of the questions that I particularly appreciate are: Why do humans keep repeating a history of war? Is killing justified for the sake of loved ones? How can world peace be achieved? What is the root cause of the world's lack of harmony? As individuals, what should we care about? Do all individuals harbor fears and end up closing themselves within walls, brainwashing themselves to distort the outside world beyond those walls?

It is a fantastic anime that excels in world-building, character development, thematic reflections, and narrative storytelling. However, being an epic-length animation, it is destined not to be flawless. The lengthy and dragging plotlines, abrupt shifts in the protagonist's motivations, imperfect back-and-forth timeline transitions, overly deliberate facial expressions, monotonously gloomy art style, overwhelmingly crafted sense of fear, all of these could lead to some discomfort during the viewing process.