One of the stand-out elements in SSSS.Dynazenon that there are several storylines going on at the same time. There's the story about the mysterious kaiju and the people that can control them, the story about a man named Gauma, the strange ex-Kaiju user who has a peculiar backstory; and then there's a girl named Yume who tries to find the truth about her sister's death.

SSSS.Dynazenon is the sequel to 2018's SSSS.Gridman. It is still unclear how the two connect; however, one of the similarities between both series is their ambiguity. You won't find out what is actually going on until about halfway through the entire series. That being said, if you stick around until everything starts to unravel, you'll find a story that has both exciting battle sequences and delicate human drama at the same time.

Digimon Ghost game is about the digital monsters (Digimon) that have been harming and disturbing the humans around them, but due to their natural holographic nature, most people think that they are being attacked by ghosts. Our protagonists, Hiro and Gammamon, decide to help both the humans and Digimon that were involved in these various ghost incidents.

This iteration of Digimon is easily one of the better ones in the franchise simply because it's not hard to imagine the technologies in our real world, such as Augmented Reality and Virtual Reality, to soon evolve into something that resembles the world in this anime, and that is what makes it such an interesting sci-fi concept.

After World war III, the government decided to ban every religion and any kind of spiritually-focused activities. To enforce that ironclad rule, they created a Special Weapon Enforcement Division that consists of only the very best people that are equipped with the bleeding edge technology.

One of the notions imposed upon the citizens is that there is no such thing as psychic powers. Nevertheless, when one of the enforcers himself begins to awaken a powerful telekinetic power, he begins to question his life-long beliefs. That is when the tangled web of politics and conspiracy finally begins to unravel. The combination of fast-paced action sequences, interesting settings, and intricate mystery makes Night Head 2041 one of the most exciting sci-fi anime of 2021.

Edens Zero is the story of Shiki and his friends as they embark on a journey to explore every corner of the cosmos. They meet the notorious space pirate, deal with a time-traveling mad scientist, engage in battle against the Interstellar Union Army, and retrace the steps of Shiki's grandfather who happens to be the legendary Demon King. They travel from one planet to the next and meet quirky people along the way as they drift on board the mythical warship called Edens Zero.

Edens Zero is basically Fairy Tail in space. Not only because both titles were created by the same mangaka, but there are also many similarities between the two, such as the happy-go-lucky protagonist, cute mascots, scantily-clad women, the fight between good and evil, and also a heavy emphasis on friendship and family. The only difference is instead of the magic and sword in Fairy Tail, Edens Zero has A.I., robots, and planetary adventure.

After the end of world war II, the Republic of Zirnitra (similar to USSR) engaged in a space race with the Kingdom of Arnak (similar to the US) with the ultimate goal of moon landing. However, rather than training chimpanzees before sending humans to space like the Kingdom of Arnak, Republic Zirnitra decided to send a vampire named Irina Luminesk instead. After all, vampires have similar physiology to humans but nobody will be upset if the experiment fails and the foul creature is killed.

Irina: The Vampire Cosmonaut has two main characters, the vampire Irina and the human who takes care of her, Lev Leps. The first part of the series focuses on Irina's training as a cosmonaut, while the second part focuses on Lev's preparation. Other than the space race, this anime also deals with the matter of prejudice and hate against vampires. That additional layer of storyline makes this series feel like a true sci-fi/fantasy that is still firmly grounded in reality.

In the first season of Dr. Stone, we saw the modern world engulfed in a mysterious light that petrified every living being. Thousands of years later, a genius boy named Senku accidentally turns back into a human and immediately begins to rebuild human society through the power of science. Tsukasa is a physically-gifted boy that Senku de-petrified by using the revival fluid. Unfortunately, the two of them end up having a disagreement over the future of humanity. The first season ended in a clash between Senku's kingdom of science and Tsukasa's kingdom of might. This second season Marks the beginning of the last phase of the wars between the two stone kingdoms. There will be crazy fights, cunning strategy, lies, spies, and deception.

Dr. Stone is a unique sci-fi story because rather than creating new inventions for the future like any other sci-fi series, Senku sought to recreate our current technology using what is available in the modern stone age. That premise alone makes it deserving of its position on this list.

Megalo Box is a sport where boxers fight by using an exoskeleton on their arms. It is the most popular sport in an alternate modern-day Tokyo. In the first season, we followed the story of an underground fighter named Joe who fought his way to the top without an exogear and became the legendary world champion against all odds.

The second season begins roughly five years after the end of the first. A devastating event that happens between the first and second seasons creates a rift between Joe and his teammates. He feels overwhelming guilt and drowns himself in drugs and alcohol while being a traveling underground boxer. This is the story of how Joe tries to get back on his feet, rekindle his estranged relationship with his teammates, help another boxer as a coach, and even try to regain his crown as the champion. That being said, the only sci-fi elements within Megalo Box are the exoskeleton arm sleeve and all the technology around it, which is why it doesn't get a higher ranking in this list despite being one of the best anime in 2021.

World Trigger is an anime about an organization called Border that is responsible for the Earth's defense against alien monsters called Neighbors. The people who work as soldiers for Border are trained to use their biological power called Trion and channel it through the weapons that can utilize that energy called Triggers.

Osamu has one of the lowest amounts of Trion in Border and yet he strives to do all that he can to be useful for his teammates. The first season ends with a large-scale attack of Neighbors into Border's territory while the second season begins with a small-scale guerilla attack from Human-like Neighbors. The third season, however, focuses heavily on a team championship called Rank Wars between the members of Borders in order to increase their skill and team ranking.

World Trigger manages to come up with an interesting twist to the familiar aliens-attacking-earth storyline. The concept of Trion and the numerous ways to utilize it make the battle sequences highly tactical and dynamic at the same time. That is why World Trigger is such a great sci-fi anime.

The Republic of Magnolia has been constantly at war with its neighboring nation for years. However, while the general public lives their carefree life in the city, the ones that fight in the front lines are actually a group of Marginalized people called the 86. For each squadron of 86’s soldiers, there will be one handler from the official Magnolian officer.

The first season focuses on the relationship between one of the elite 86’s squadrons led by a man nicknamed "undertaker" and their handler, a novice Magnolian officer called Lena Milize as they go through increasingly difficult battlefields and lose their comrades one after the other. The second season sees the remnants of the elite squad now fighting under different banners and for a vastly different goal. 86 is a bloody and heart-breaking anime that seamlessly combines suspenseful tactical battles and heart-wrenching human drama at the same time, and that is why this is one of the best sci-fi anime in 2021.

In the distant future, there will be a brutal war between humanity and AI. In order to prevent it from happening in the first place, a scientist sends a crucial mission to the first autonomous AI ever made, Diva the singer, who lived 100 years in the past. Accompanied by an AI from the future called Matsumoto, Diva is tasked to change the course of certain events within the past 100 years that can be the catalyst to the massive war in the future.

Vivy: Fluorite Eye's Song is an anime with a beautiful blend of different themes and genres. There are sci-fi elements, such as AI, time-traveling, and space hotels, and also action, comedy, espionage, musicals, and even politics. Vivy: Fluorite Eye's Song found a way to cram all of these different story elements and also utilize them in a way that is creative and interesting, and that is the reason why Vivy: Fluorite Eye's Song deserves the crown as the best sci-fi anime in 2021.