The Dragon Ball Z movies aren’t exactly known for being original. The average film in the franchise heavily lifted from whatever was happening in the anime at the time, resulting in a roster of movies that feels more like “Dragon Ball Lite” than any real attempt to turn Dragon Ball Z into a theatrical experience.
For what it’s worth, the Dragon Ball Z movies are still entertaining diversions from the main story – they’re just too reminiscent of the main story. While the best Dragon Ball Z movies overcome such flaws, there are too many instances of the films ripping off the anime wholesale.
10 Gohan’s Kidnapping
Dead Zone heavily styles itself around the confrontation with Raditz at the start of the Saiyan arc, complete with Goku and Piccolo teaming up to fight Garlic Jr. by the end of the movie. Egregiously, Dead Zone also features Gohan’s kidnapping from the original series, albeit without the same dramatic weight.
Garlic Jr.’s henchmen kidnap Gohan for the Dragon Ball on top of his hat, spurring Goku to go after Garlic Jr. Like in Dragon Ball Z, Piccolo teams up with Goku after an earlier encounter with the villain(s) that left him shaken. And just like in the Saiyan arc, the kidnapped Gohan ends up playing a key role in saving the day.
9 Almost Everything About Tullece
Tullece is really an amalgamation of Goku, Vegeta, and Raditz. Tullece literally looks like Goku, which in turn gives him an inherent familial connection to Goku ala Raditz (although the movie itself never actually comments on any relation between the two characters,) while he functionally fills the same role Vegeta did during the Saiyan invasion as the figurehead. Tree of Might is basically just Toei’s version of the Saiyan arc where nobody dies.
8 Lord Slug’s Motivation
Tullece was pushing it in terms of originality, but being an amalgamation of several characters still results in a fairly unique figure. Plus, Tree of Might is actually one of the more original movies in the series in terms of plot, framing, and atmosphere. Lord Slug, on the other hand, is not.
Slug himself is just a retread of Demon King Piccolo, but with all his personality and personal history in the series’ lore stripped out. Like Piccolo, Slug wants to restore his youth so he can once again be in his prime; and like Piccolo, it doesn’t take too long for Slug to be put in his place.
7 Cooler’s Base Design
Tullece’s design heavily lifts from Goku, but the idea of creating an evil double of the main character is a common enough trope where it’s not that bewildering. Lord Slug copies Piccolo Daimao wholesale, but he hadn’t been relevant in quite a long time so it can (but shouldn’t) be read as pure homage.
Cooler is another matter entirely. While Cooler’s final form is incredibly unique and makes him stand out from Frieza, his base design is simply a more masculine version of Frieza’s final form. Disappointingly, Cooler would return with his base form in The Return of Cooler.
6 The Android Attack
Movie 7, Super Android 13, isn’t hiding the fact that it’s ripping off the Android arc, but it has some fun with it. Chronologically, the movie sets itself after Androids 16, 17, and 18 have been defeated. Cell seemingly never showed up and Goku’s recovered from the Heart Virus just fine. All's right with the world until Androids 13, 14, and 15 suddenly attack.
Super Android 13 styles itself as a version of the Android invasion where Goku is allowed to participate and the Dragon Team are actually in the right place at the right time to prevent any major damage from being done.
5 Android 13’s Perfect Form
Beyond his inexplicable design, there isn’t much to Android 13’s character. The Funimation dub goes out of its way to give 13 some actual personality, but he’s one of the flatter villains in the Japanese original. Android 13 also suffers from ripping off Cell rather blatantly. Just like Cell, Android 13 reaches his perfect form when absorbing two other Androids: in this case 14 and 15. Android 13 absorbs his fellow Androids at the end of the film, becoming Super Android 13.
4 The Bojack Tournament
Just like the Cell games, the Intergalactic Tournament features in Bojack Unbound is a pseudo-tournament that’s ultimately interrupted and was never meant to be a proper tournament to begin with. In both tournaments, Gohan is ultimately the last man standing and ends up defeating the main antagonist (Cell/Bojack) only through the help of his father. The main difference being that Goku’s intervention is psychological against Cell and actually physical against Bojack.
3 Super Saiyan 2 Gohan Vs Bojack
Only after everyone in the supporting cast has been beaten into submissions by Cell’s/Bojack’s minions, Gohan is left at the main villain’s mercy. In both instances, he’s pushed to a breaking point where he taps into Super Saiyan 2 and ends up killing every single one of the villain’s henchmen.
Super Saiyan 2 Gohan finishes off both Cell and Bojack with a super charged Kamehameha – the key difference being that Gohan isn’t one handed when finishing off Bojack. In either case, Super Saiyan 2 Gohan is strong enough where he can kill his opponent with ease.
2 Fat Janemba
Just like Majin Buu, Janemba was a lean demon hell bent on causing chaos who had their murderous nature warped after absorbing a purer soul. Where Majin Buu absorbed the Dai Kaioshin and became considerably more passive, Janemba ended up merging with an ogre down in Hell.
Fat Janemba is just Fat Buu without a personality. Both are childish and don’t understand the magnitude of their actions, but Buu has an actual character arc that helps him grow into a main character whereas Janemba is just a one off movie villain.
1 Super Janemba
After Super Saiyan 3 Goku manages to defeat Fat Janemba, the demon transforms into his true form. Clearly demonic and now wielding a sword, Super Janemba is far too strong for Super Saiyan 3 Goku to handle on his own. Goku and Vegeta are forced to rely on fusion, becoming Gogeta in the process. Notably, Gogeta’s appearance predated Vegetto’s, so Fusion Reborn’s take on the character would actually be rooted in Gotenks (which also makes sense considering Gotenks fights Super Buu whereas Vegetto fights Buuhan.)