Ultraman R/B is a 2018 tokusatsu series created by Tsuburaya Productions and the 30th entry in the Ultra Series, as well as the final entry of the Heisei generation of Ultra heroes due to Emperor Akihito (Emperor Heisei) stepping down as the incumbent Emperor of Japan to be replaced by his son, Prince Naruhito.
In a notable difference from previous series, rather than a single Ultra as the main protagonist (with the occasional Second Ultra who shows up later), it focuses on a pair of Ultra brothers, Ultraman Rosso and Ultraman Blu, and their human hosts Katsumi Minato and Isami Minato. Katsumi and Isami are two brothers (with Katsumi being the elder one) who live with their younger sister and their father who runs a specialty store. One day, during the sudden appearance of a giant monster, the brothers find the R/B Gyro, which grants Katsumi and Isami the power to become Ultraman Rosso and Blu respectively. Using the power of R/B Crystals that allow them to transform and change forms based on the elements and previous Ultra heroes, the brothers face their emotions with allies and enemies, grow up and confront powerful enemies, and realize the importance of those bonds that they take for granted.
Ultraman R/B provides examples of the following tropes:
- Bookends: Of the entire Heisei Era Ultra Series as a whole, with this one being the last before Emperor Akihito abdicated his throne. Ultraman Tiga was the first and only of the Heisei Series to actually focus on a Halloween-themed episode, until R/B came along.
- Cerebus Retcon: The show's opening theme reveals a shooting star that fell upon Ayaka City, which was the foundation of that city's origin. As the story goes on, its revealed that said meteor was a pair of brothers and their sister falling from the sky after attempting to protect Earth, resulting in the brothers' deaths, their powers inherited to the Minato siblings and their sister survived but turned into a vengeful Well-Intentioned Extremist Omnicidal Maniac.
- Colorful Theme Naming: Rosso and Blu are named for the Italian words for red and blue. And then there's Grigio Bone, whose name being Italian for "gray" and Ultraman Orb Dark's full name (Noir Black Schwarz) is three different languages for the color black.
- Contrasting Sequel Main Character: Like Riku, Katsumi and Isami's story heavily involves the concept of family, except where Riku was related to Ultraman Belial and had a...complex relationship with him (on top of him not being Belial's son in the traditional sense), Katsumi and Isami are brothers, and appear to be on good terms with their father and sister.
- Decon-Recon Switch: The first half of the series is a deconstruction of the more recent Ultra Series, wherein instead of the main villain aiming for an even more malicious plan by orchestrating monster attacks, Makoto Aizen is portrayed as a Heroic Wannabe and a darker take on the Ascended Fanboy trope who wants to be an Ultraman because of his childhood dream, with all those monster attacks on the city he orchestrated and antagonism towards Rosso and Blu were all out of what he considered as a popularity contest. By the time Saki Mitsurugi rolls in, she displays a bigger threat by ousting Makoto and took his place as an even more threatening villain with a rather justified reason to destroy Earth in hopes of defeating an Ancient Evil Planet Eater Eldritch Abomination and avenge her brothers' deaths. Her arc in the story puts the titular Sibling Team in a dilemma to defeat Reugosite while saving Earth at the same time.
- Elemental Powers: The Ultramen have different forms based on the four classical elements: Flame, Aqua, Wind, and Ground.
- Fire/Water Juxtaposition: Rosso favors Flame form, while Blu defaults to Aqua.
- Foolish Sibling, Responsible Sibling: Although Isami is the genius of the two, it was Katsumi who tends to be the straight man. Unfortunately, their bickering can also be a detrimental in the middle of a fight against Kaiju.
- Foreshadowing: In episode 3, Rosso and Blu fought against Gargorgon and the latter was briefly petrified. Episode 23 shows a Bad Future wherein the brothers fought against Reugosite in its gaseous state and were petrified to death. Thankfully this future was averted in the final episode.
- Grand Finale: Of the franchise's Heisei era, since Emperor Akihito was succeeded by Prince Naruhito.
- Halloween Episode: Episode 17. There's a special Halloween arrangement of the opening theme, and friendly aliens wanted to organize a party at a spooky mansion.
- Japanese Beetle Brothers: Their design carries a bit of the motif, as Rosso has two horns on his head while Blu has one.
- Lighter and Softer: This series explores the theme of family, and even has a lot of comedic moments in the battle against Ultras and monsters.
- Missing Mom: The Minato siblings lose their mother Mio 8 years before the series begins. Her disappearances leads to Katsumi quitting his dream as a baseball player to support his dad's business, Isami to study in a college and follow her footsteps while Asahi took over the role in housekeeping.
- Promotion to Opening Titles: Once Mio finally returns in The Teaser of episode 22, she finally gets promoted to appearing in the opening credits sequence starting with said episode.
- Red Oni, Blue Oni: Unsurprisingly, Rosso and Blu have this dynamic. Their (default) colors even match the trope name.
- Sibling Team: The unique aspect of the series: rather than a single Ultra as the protagonist, Rosso and Blu are brothers working together. While not the first Ultra to have a brother help them (Ace and Taro were adopted brothers and Leo had his brother Astra), this is the first time they share billing as protagonists rather than just sporadic appearances.
- The series actually features two of these; Rosso and Blu are brothers, and so are their respective human hosts, Katsumi and Isami.
- Special Edition Title: In Episode 17, the theme is rearranged with a spooky yet upbeat Halloween arrangement, and clips from the episode play for a few seconds.
- Spiritual Successor: Much like with Ultraman Orb being one to Ultraman Tiga and Ultraman Geed being one to Ultraman Dyna, R/B continues the trend by being one to Ultraman Gaia, due to its focus on two Ultras, as well as ditching the transformation gimmick from the previous series (Gaia ditched the Type Change gimmick present in Tiga and Dyna, and R/B ditches the idea of fusing powers used by 2 different Ultras that Orb and Geed featured). It even debuts in the year that Gaia turns 20!
- Red and blue siblings who fight against monsters makes them very similar to Space Ironmen Kyodain and the 1985 series Kyodai Ken Byclosser, especially in the case of Byclosser, since both were granted powers by a being from outer space.
- The R/B Gyro is designed similar to the Matrix of Leadership, right down to its opening mechanism.
- The episode recap is done similarly to Kamen Rider Build with two characters commenting on the events in a meta sort of way.
- The quote on Katsumi's white undershirt, "We should seek the greatest value of our action", is a quote by Stephen Hawking.
- Transformation Trinket: The R/B Gyro, which both brothers use to transform, along with the R/B Crystals. Makoto Aizen, the initial sole Big Bad can transform into Grigio Bone with its crystal or uses the Orb Ring Neo to become Orb Dark.