Dragon Ball: Plan to Eradicate the Saiyans (サイヤ人絶滅計画, Saiyajin Zetsumetsu Keikaku; lit. "Dragon Ball Z Side Story: Plan to Eradicate the Saiyans") is the fourth installment of the Gokuden series of Famicom games with a completely original plot as opposed to what came before it. It later was adapted into the first Dragon Ball Z OVA as a visual guide to the original game. The OVA was later remade into a shorter but updated bonus movie for Dragon Ball Z: Raging Blast 2.
Dr. Raichi is one of the only survivors of the Tuffles, who were massacred by the coming of the Saiyans in the original anime adaptation. Raichi managed to escape with a capsule and found refuge on the Dark Planet, a world at the end of the universe. Now, his only wish is to eradicate the last remaining Saiyans, using a deadly substance known as "Destron Gas" to slowly destroy all life on planet Earth.
While an Excuse Plot in general, the core ideas and concept were later better explored in Dragon Ball GT, which also includes the Tuffles and a villain who was no better than the Saiyans he so detested, and Dragon Ball Super, where a Tuffle and another warrior who greatly resembles Hatchiyack, Aniraza, appear in the Tournament of Power.
This work contains examples of:
- Adapted Out: The remake cut out a lot of scenes from the original such as taking out the surrounding Destron Gas emitters and the journey to the Dark Planet.
- Advertised Extra: A lot of emphasis is put on Hatchiyack in the marketing rather than Raichi. Justified, since Raichi is more of a Non-Action Big Bad, and Hatchiyack is a fighter, which better suits the franchise.
- Attack of the 50-Foot Whatever: Hatchiyack in one of the OVA's multiple paths.
- Back from the Dead: The ghost warriors at the final Destron Gas emitter.
- Big Bad: Dr. Raichi.
- Big Damn Heroes: Vegeta and Trunks decide to drop in on the party at the glacier and help destroy the Destron Gas emitter there.
- The Brute: Hatchiyack once he transforms from a supercomputer to a humanoid being.
- Emerald Power: Hatchiyack's energy glows an emerald green, kind of like a certain Legendary Super Saiyan...
- Excuse Plot: As expected from a videogame story, the plot is very thin, even by Dragon Ball Z standards. This also applies to the appearances of Frieza, Cooler, Turles, and Slug. While it's understandable why Frieza and Cooler came back, the other ghost warriors that came back are clearly just there because they were popular at the time and are poorly mixed in.
- Expy: Hatchiyack is basically Broly if he had a science-oriented origin story... Before such a thing actually happened in Bio-Broly.
- He Who Fights Monsters: It's clear that Raichi let his obsession with getting revenge on the brutal Saiyans get the better of him and made him go too far.
- Mad Scientist: Dr. Raichi.
- Make My Monster Grow: Hatchiyack's super form.
- Misplaced Retribution: Raichi's plot to eradicate all Saiyans will also take out all of the humans, who were otherwise mere bystanders.
- Mook: Strange aliens who originally were just there to fulfill the random encounter quota.
- Multiple Endings:
- Hatchiyack was originally a Bonus Boss for defeating Raichi without using items. The OVA took the approach of making both scenarios possible depending on what actions are taken, but given that the remake only follows the Hatchiyack path, that's supposedly the canon one.
- The original OVA also had a lot of different approaches as to how Hatchiyack could be defeated, including the aforementioned giant Hatchiyack, but again, the remake makes the timing puzzle the canon ending.
- Save the World: The Z-Warriors have to save the world from a vengeful alien scientist.
- Send in the Clones: Hatchiyack in one of the multiple paths.