Two heads are always better than one and having a partner in crime can be handy. The same goes true for anime and even other entertainment media. The power of siblings is not to be trifled with, assuming they aren't constantly bickering with each other, of course. Certain anime have even made the premise all about these brother/sister duos regardless of how good or evil they are.
You can bet that these brother/sister duos are formidable; their resounding on-screen presence is always welcome and irreplaceable. There are plenty of them in many different anime, but not all have powers or make an impression. Those that do will forever be immortalized in the anime sibling Hall of Fame. We have compiled ten of those dynamic duos; siblings that will make you wish you have an onii-san or onii-chan.
10 SORA AND SHIRO (NO GAME NO LIFE)
Even recluses can be powerful in their own way. Sora and Shiro from No Game No Life have proven this many times over. Sora is the older one-- an 18-year-old male and Shiro is his 11-year-old little sister. Together as hikikomori (recluse) step-siblings, they have dominated the online gaming scene with their skills and coordination.
The two of them somehow ended up in a world where games are everything thanks to a god named Tet. Even then, the two complementary gamer step-siblings still managed to perform what they do best, which is win at games.
9 KOHAKU AND SANGO (INUYASHA)
Fans of Inuyasha can't miss these two dramatic siblings. Somewhere along their journey, they both join Inuyasha and Kagome's party throughout their adventures in mythical feudal Japan. Sango is the older sister while Kohaku is her initially frail little brother. Both of them were trained by their clan to be demon slayers and they do it quite well.
Of course, Sango being the older of the two has better skill and expertise. Over time, Kohaku manages to improve and become a respectable opponent whether his enemies are humans or demons.
8 EREN AND MIKASA (ATTACK ON TITAN)
By name alone, we can already surmise that Eren Jaeger and Mikasa Ackerman are not related by blood. Mikasa was actually orphaned by Eren's family, meaning they are only step-siblings. Nevertheless, the two are like peanut butter and jelly in Attack on Titan. Both suit each other well in demeanor and skills.
Mikasa, the big sister, is perfect in terms of human limitations, meaning she's more skillful than Eren. Meanwhile, Eren has the ability to turn into a titan, making him a central asset in the anime. The two both share a traumatic past-- one that involves murder through self-defense and such a life event has strengthened their bond.
7 RIN AND YUKIO (BLUE EXORCIST)
It doesn't matter what race siblings are, there will always be some jealousy and suppressed emotions involved between them. Rin and Yukio from Blue Exorcist are only half-human; they're 50 percent demons, which makes their emotional tension more complicated. Yukio is the kinder and younger among the two of them and also upholds his duty of protecting his brother quite religiously.
Rin is... he's the direct son of Satan. You can guess what his behavior is based on his parentage alone. These two are basically Yin and Yang, where Yukio equalizes Rin's hotheadedness with a calm and happy disposition which is crucial whenever the two are facing demonic threats.
6 ELRIC BROTHERS (FULLMETAL ALCHEMIST)
These two are probably what will come to mind for most anime fans when sibling duos are concerned. So here they are, Edward and Alphonse Elric from Fullmetal Alchemist and its Brotherhood version. These two have gone through seemingly insurmountable ordeals in their childhood, perhaps even more so than most brother/sister duos here.
Al lost his whole body while Ed lost an arm and leg while both of them were trying to resurrect their dead mother. Despite the nightmares they experienced at such a young age, they still went on to be two of the most accomplished alchemists in a fictional industrial age Germany. There's no doubt that these two needed to be here as they can even bend matter to their will and weaponize anything.
5 GAARA AND TEMARI (NARUTO)
Technically, the sand siblings of Sunagakure in Naruto/Shippuuden consist of three blood-related ninjas: Gaara, Temari, and Kankuro. However, we can only have two of them here, so it's all down to Gaara and Temari since they are close to each other and often leave Kankuro in the sidelines.
Gaara is similar to Naruto; he holds a jinchuriki (destructive giant monsters) which gives him immense power but also makes him unstable. When that happens, Temari usually has to take good care of his emo little brother. After all, Gaara is the youngest of the three of them. With that said, Temari herself is no slouch when it comes to being a ninja, she's quite proficient with her giant razor wind fan and can prove to be a deadly opponent.
4 RYUKO AND SATSUKI (KILL LA KILL)
Most viewers and fans don't get to find out that Ryuko and Satsuki from Kill la Kill were siblings until near the end of the anime. Hence, the two weren't always a good tag-team duo. In fact, they fought quite a lot before the two were revealed to be siblings. Even so, Ryuko never really had any intention of causing harm to Satsuki; the latter also shared the same sentiment.
By the end of the anime, the two finally decided to set their differences aside and help each other defeat a more powerful enemy. Since then, they have displayed a more sisterly relationship compared to their prior interaction in the show. It was through their team-up that they were able to defeat the all-powerful antagonist of the show, Ragyo, and her rainbow hair.
3 KAMINA AND SIMON (GURREN LAGANN)
You'll find no other brotherly duo (other than the Elric brothers) that would make your cry manly tears than Kamina and Simon from Tengen Toppa Gurren Lagann. Simon was a meek and shy kid until he met the proud and brave Kamina, who instantly declared him as his brother (despite both not being blood-related). Together, the two forged a dream of returning to the surface of the Earth after aliens forced human beings to live underground.
With the help of a mecha head part which Simon dug up and controlled and the mech body Kamina piloted, the two set out to form their own army to fight their alien oppressors and reclaim mankind's dignity. This is one of those anime where you would wish someone could purge from your memory just so you can watch it again with all the twists and turns. In short, go see it if you haven't... now.
2 ANDROID 17 AND ANDROID 18 (DRAGON BALL Z)
When you and your sibling are feared even by Super Saiyans, you know you deserve to be near the top of this list. Android 17 and 18 from Dragon Ball Z were initially human twins named Lapis and Lazuli respectively. They were turned into godly Androids thanks to the twisted scientist Dr. Jero whose main goal for conceiving them was to exact revenge against Goku.
The two of them proved to be more than Dr. Jero could handle; they killed their own creator but still went after Goku and friends. Turns out, they were leagues above Goku's friends (Yamcha, Tien, Krillin, Piccolo, etc.) and were worthy opponents to Super Saiyans. Too bad Cell came along and put an end to their rampage prematurely
1 GOHAN AND GOTEN (DRAGON BALL Z)
Thanks to Goku's sons, Gohan and his younger brother Goten, you can do a "fusion dance" with your little sibling without much embarrassment. That's one of the perks of having a sibling on the same wavelength (and power level) as you are; you get to invent cool new moves and trends together.
In that regard, Gohan and Goten are the ultimate Super Saiyan power duo we never had as canon. On their own, they're worthy descendants to Goku. Together (in their fusion mode), they might even be a viable substitute for their father in terms of power. It's too bad their fusion only occurs in a game, namely Dragon Ball: Raging Blast 2 and it was even done lazily there, displaying Gotenks (Goten + Trunks) instead. Regardless, these two are the most powerful brothers in the universe.