From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Cell Junior (セル ジュニア, Seru Junia; FUNimation "Cell Jr.", Viz "Cell Jr.") is a miniature version of Cell in his Perfect form.
Dragon Ball Z
Cell Juniors were created by Perfect Cell during the Cell Games in order to infuriate Son Gohan enough to release his hidden power. Cell then had them attack Son Goku, Vegeta, Future Trunks Brief, Piccolo, Kuririn, Tenshinhan, and Yamucha. In the dubbed anime, they are said to have the same strength as Perfect Cell himself, albeit with substantially less durability (this claim was never made in the manga). They were extremely powerful, facing the Z Warriors without fighting seriously. Two of them easily beat on Tenshinhan and Yamucha (one of them even broke Yamucha's arm), another two beat on Kuririn and a tired Goku, three of them were fighting on par with Piccolo, Vegeta, and Trunks, and one was even strong enough to catch Vegeta's Final Flash and throw the attack to the side (this is in a filler portion of the anime as this did not happen in the manga). After Gohan became infuriated by the Cell Juniors' assault on the Z Warriors coupled with Cell's killing of Artificial Human No. 16, however, his hidden powers awakened and he transformed into a Super Saiyan 2, allowing him to easily kill the all of the Cell Juniors one by one with effortless blows.
Cell Junior has appeared as a playable character in the Budokai video game series, the Budokai Tenkaichi video game series, and Dragon Ball: Raging Blast 2.
The following are moves that have been performed by the Cell Juniors (or are highly implied and speculated to be usable):
- Death Beam (possibly) — A move that Cell Juniors has possibly passed down through genetics from Cell as an imitation of Frieza's Death Beam. They never used the move in the anime or the manga.
- Ki Blast
- Kienzan — A move that Cell Juniors has passed down through genetics from Cell as an imitation of Krillin's Destructo Disk. It was used against Gohan in the anime and never used in the manga.
- Kamehameha — A move that Cell Juniors has passed down through genetics from Cell as an imitation of Goku's Kamehameha. It was used against Gohan in the anime, never used in the manga, and used in Dragon Ball Z: Budokai Tenkaichi 3.
- Super Kamehameha – A advanced version of the Kamehameha. While never used in the anime or manga, the attack is their Ultimate Blast in Budokai Tenkaichi 3.
- Regeneration — When a body part is cut or blasted off, they use this to heal themselves back. It can be used if they are hurt. Unlike Cell, however, they do not regenerate when their heads are no longer intact. This technique also requires a bit of energy to perform, and all users are seen panting and huffing after performing the process. It should be noted that while we do see Cell regenerating multiple times throughout the series, we never see the Cell Juniors do it.
- Special Beam Cannon — A move that Cell Juniors has passed down through genetics from Cell as an imitation of Piccolo's Special Beam Cannon. It was used against Gohan in the anime, never used in the manga, and used in Budokai Tenkaichi 3.
- Tri-Beam — A move that Cell Juniors has passed down through genetics from Cell as an imitation of Tien's Tri-Beam. They used it against Gohan in the anime and was unused in the manga.
- The Cell Juniors, Bio-Men, and Saibaimen all share similarities. They are short, work in groups, and pose a moderate threat at their introductions, but are easily disposed of later. Unlike the Bio-Men and the Saibaimen, however, the Cell Juniors are all able to speak in the anime. One of them even has a single line in the manga (like how Kid Boo and Evil Boo are in the same series, but not the manga), though they do so very rarely (the bulk of their lines as well as their only line in the manga consists of "over here", however, they also say the names of their attacks and yell "come get me").
- A slight error is made in the number of Cell Juniors that Gohan kills in "The Unleashing". If you count them in the episode, Toei has Gohan kill eight Cell Juniors even though Cell only creates seven. This error is not present in the original manga.
- The Tri-Beam is the only attack that the Cell Juniors use that Cell himself is never shown using on-screen.