All spoilers for Avataro Sentai Donbrothers VS Zenkaiger and Ohsama Sentai King-Ohger are unmarked. You Have Been Warned!

For some reason, the Donbrothers have ended up on Tikyū! While they try to figure out how they got there, the Ohsama Sentai are very wary of them. Soon afterwards, both teams end up in Hākabāka under various circumstances. Everyone comes to blows with each other as Gira marks the Donbrothers as enemies, blaming Taro for them all dying. As one team tries to beat the other, one abyssal truth may just unite them...

The film provides examples of:

• Affectionate Parody: The movie is a very self-aware variation on the typical inter-series crossover between two Sentai teams, as well as skewering some notable isekai fiction genre tropes.
• Birds of a Feather: The movie makes it a point to match similar members from each team with each other.
  • Taro and Gira get matched as the respective Reds of their teams.
  • Shinichi gets matched with Yanma and Jeramie due to their matching colors (and contrasting personalities) and their shared fondness for literature respectively.
  • Haruka and Sonoza get matched with Hymeno and Rita due to their shared interests in fiction (manga for the two Donbrothers, and the Moffun TV series for the two monarchs).
  • Jiro and Kaguragi get matched due to their shared status as the most physically built members of their teams.
  • Tsuyoshi is paired with Rcules since the two are married men.
• Brick Joke:
  • The Ninjark Sword/Don Murasame can be seen lodged under the car that ran Minoru Ohno over. Near the end of the film, the car has been moved and right as Ohno revives, Murasame takes the chance to discreetly fly away before anyone can see him.
  • The Stinger of the last crossover movie implied something happened to Sonoi after he revived Taro, but kept it vague. This film reveals what happened: He died.
• Call-Back:
  • Taro is in Tikyū mainly to find his old beetle Gii. Near the end it's revealed to be in Hākabāka under the care of Sonoi.
  • Taro sends himself to Hākabāka by lying about his fondness for Gii; Donbrothers established that Taro dies (albeit temporarily) when he tells a lie.
  • Minoru Ohno, long standing enemy of the Donbrothers, returns yet again, back in his Ohsama-Ki form.
  • Yanma attaches the Thundercaller used in #12 and #21 on both Jeramie and Saruhara.
  • Tsuyoshi freaks out about King-Ohger due to being traumatized by his fight with it from its Early-Bird Cameo in Episode 45.
  • While in Hākabāka, Taro runs into Sonoi at his oden stall.
• Commonality Connection:
  • Subverted with Saruhara and Jeramie. The two seemingly bond over poetry, overwhelmingly complimenting each other. Yanma attaches them to the Thundercaller to reveal that the two were lying to each other the whole time.
  • Jiro and Kaguragi immediately bond over their shared love of fitness and immediately challenge each other to a wrestling match. During the battle between the teams later, this ensures they're the only two mostly having fun.
• Cruel to Be Kind: After Taro and Gira leave, Sonoi turns behind him to reveal that Taro's pet Gii was there the whole time and was deliberately avoiding Taro, as Taro should be with the people he actually needs.
• Curb-Stomp Battle: Ohsama-Ki manages to kill Haruka, Hymeno, Rita and Sonoza off-screen and send them to Hakabaka. He's on the receiving end when the teams take out their collective frustration on him.
• Death Is Cheap: Fortunately for both teams, getting out of Hākabāka is a relatively simple matter — though in Gira's case he only revives once Boone gets the kibi-dango out of his throat.
• Denser and Wackier: The movie eschews King-Ohger's serious tone for Donbrother's typical brand of Surreal Humor and hamminess. Funnily enough, despite the film not being written by Toshiki Inoue (it was instead written by King-Ohger's head scriptwriter Minato Takano), the Donbrothers cast noted in multiple interviews that the movie's script felt ripped straight out of the series.
• Deus ex Machina: Zenkaizer Black makes a sudden appearance in Hākabāka to give Taro and Gira the obligatory crossover power ups.
• Don't Look Down: Tsubasa and Sononi meet their ends when they look down and realize they're right above a hole in one of Shugoddam's bridges.
• Enemy Mine: Ohno appearing in Hākabāka leads both the Donbrothers and Ohsama Sentai to beat him up simply because he's interrupting their respective battles with each other. It ends up causing both teams to end up bonding.
• Five-Second Foreshadowing: Gira is trying out some kibi-dango from Toufu (and ends up choking on one, leading to his death and arrival at Hākabāka) just as Taro arrives to give him a package meant for him. Taro, of course, is associated with kibi-dango due to their mutual association with the Momotarō legend.
• Freeze-Frame Bonus: If one looks closely at the scene where Ohno was hit by the truck, one can spot the Ninjark Sword right under the truck, as if the sword was the cause of the accident. However it doesn't build up to any cameo for Don Murasame, as the sword later simply floats by the newly-revived Ohno during the end credits.
• Friendly Rivalry: When the teams inevitably clash, Kaguragi and Jiro are the only two without a grudge against one another and simply use the battle as an excuse to test each other's physiques out more...until Dangerous Jiro comes out, at least. After the fighting, this is played straight and the two teams end the film having fun in the kingdoms.
• Ham-to-Ham Combat: Taro and Gira, but also both Kaguragi and Jiro.
• Headbutting Heroes: The immense egos on both teams leads them to clash almost immediately after they first meet each other.
• Hoist by His Own Petard: Yanma puts the Thundercaller on Shinichi's and Jeramie's heads, annoyed at their bonding over poetry and realizing off-screen that the both of them are compensating for their distaste for each other. Unfortunately, the two of them grab Yanma as they're being electrocuted, sending all three of them to Hākabāka.
• How We Got Here: The movie opens with everyone about to fight in Hākabāka with it rewinding to how they got here in the first place — by showing the unusual demises the members of both teams went through, narrated by Haruka and Jeramie.
• Identical Stranger: Sononi and Tsubasa get pursued by Officer Asada on Earth. While stuck in Tikyū, Sononi and Tsubasa still end up getting pursued due to them looking like a pair of wanted criminals in Shuggodom (named Inunuka Twobasa and Sonosono Nini) — by the Shuggodom guardsman who's also played by Masashi Takada no less.
• Interesting Situation Duel: The premise. Everyone's dead thanks to Minoru Ohno stranding everyone on Tikyu and coincidences getting them killed there. The teams are so frustrated that they take it out on each other to fulfill the "Vs" portion of the title!
• Killed Off for Real: Subverted for the teams, who manage to eventually leave Hakabaka once everyone in the real world revives them. Played straight for both Sonoi and Taro's pet Gii; the former of whom was found unresponsive in his stand in the last crossover with no previous context for what happened.
• Leaning on the Fourth Wall:
  • Racules and Suzume explain the nature of King-Ohger by popping up Stock Footage from the show displaying the mech.
  • Rita, Sonoza, Haruka, and Hymeno get into a debate on whether Moffun should appeal only to kids or if all ages are allowed to enjoy the show too; reminiscent of fandom debates online on how to enjoy tokusatsu.
• Like You Would Really Do It: An In-Universe example with Moffun with Haruka stating Moffun surviving reallly isn't much of a spoiler since he is the star of a children's show.
• Mutual Kill: Kaguragi and Jiro end up sending each other to Hākabāka as their wrestling match gets a bit too energetic.
• New Life in Another World Bonus: Lampshaded. Minoru Ohno points out that as a middle-aged salaryman who got hit by a truck and thus was sent to another world, it makes him borderline invincible (just like in your average isekai manga or light novel). Unfortunately for him, he's ultimately no match for the powers of two annoyed Sentai teams.
• No Plot? No Problem!: Lampshaded, then Parodied. After the teams fight, Jeramie says that everyone should start bonding and coming together for Character Development. Everyone else isn't interested and the teams decide to simply separate politely. This leaves Gira and Taro alone for the two to encounter Sonoi's oden cart and have a moment there. During the credits later, the teams do end up bonding in Tikyu's various kingdoms.
• Offended by an Enemy's Indifference: Ohno gets annoyed that Haruka, Sonoza, Hymeno and Rita all ignore him because they're too busy debating the merits of children's fiction, which leads to him curb-stomping the four of them offscreen and sending them to Hākabāka as a result.
• Only Sane Man: Tsubasa and Sononi collectively opt to stay out of the fighting between the Sentai teams and intend to run off. Ohsama-Ki arrives and attacks them instead.
• Reincarnate in Another World: Minoru Ohno gets stuck on Tikyu after being hit by a truck. Unusually, the process isn't immediate, and it takes the Donbrothers along for the ride as well.
• The Reveal: In The Stinger of Donbrothers vs. Zenkaiger, Sonoza encounters Sonoi unresponsive in his stand; his fate left vague. This movie confirms Sonoi indeed died, implying that his final battle with Jiro was his last.
• Surprisingly Realistic Outcome: Tsuyoshi gets sent to Hākabāka by freezing to death in Gokkan because he's not wearing appropriate attire for the place.
• Taking You with Me: Played for Laughs. Yanma ends up in Hākabāka alongside Shinichi and Jeramie because they touched him just as they got electrocuted by the Thundercaller.
• Trapped in Another World: The main premise is of the Donbrothers getting stuck on Tikyū due to Minoru.
• Undignified Death: Gira dies somewhat embarrassingly in comparison to the others via choking on kibidango.
• The Underworld: The main setting is Hākabāka, which was explored back in Ohsama Sentai King-Ohger: Adventure Heaven, as well as during some parts of the final few episodes of King-Ohger.
• Unusually Uninteresting Sight: Haruka roams around the city with Sonoza, looking for inspiration for her manga. As they travel, they run into Tsubasa and Sononi getting chased by Officer Asada, but since this isn't a new occurrence to them they choose to ignore the matter at first.