As any fan of the Dragon Ball series knows, Dr. Gero has been cooking up jinzouningen (artificial humans) for the Red Ribbon Army since Goku's childhood. (What's the Red Ribbon Army?) While the man himself didn't appear until Dragon Ball Z, his creations have been running around since Dragon Ball. Dr. Gero created twenty-one different artificial humans, but we only get to see about half of them. Who were the artificial humans of Gero's creations? Let's have a look!

#1 to #7
"All had various problems." #1 through #7 are never seen in the anime or manga, and are only mentioned in the Android A B C chart in the December 2003 issue of Shonen Jump. Whether these first seven creations were all meant to serve the Red Ribbon Army or not is unknown, but it can be safely assumed that they were.

#8, Hacchan (Eighter)
Considered a "total failure" by Dr. Gero, #8 is the doc's first jinzouningen to appear in the series. Goku encounters him as an adversary during his invasion of the Red Ribbon's Muscle Towers. Why #8 is a failure in Gero's eyes is easy to see - he befriends Goku and begins fighting on his side! After the defeat of Muscle Tower, the hulking Hacchan goes to live with the mayor of the nearby village, fending it from intruders. #8 does not appear again until the end of Dragon Ball Z when he is shown lending his energy to Goku's genki dama attack.

#8's appearance might lead one to believe he shares the origins of the monstrous creation, Frankenstein, and the fact he was lending his energy to Goku is further evidence towards the idea that #8 was indeed a person once, or at least cobbbled from human parts. Whatever he is, he's one of the cutest jinzouningen Gero ever made.

#9 to #12
Every creation after #8 was built with the sole purpose of destroying Son Goku. However, #9 through #12 were all nameless, problematic failures. One can assume that they weren't total failures like #8, but they were failures nontheless.

#13, 14 and 15
The next three jinzouningen actually turn out alright. They appear in their very own movie (their only appearance, actually) and successfully follow their prime directives! Oh, the doc must have been happy. He should be — the trio is a tough bunch, activated from Dr. Gero's super secret subterranean lab (the one Trunks and Krillin didn't blow up). The trio act as a failsafe device if #17 and #18 fail. Unlike the twins, #13, 14 and 15 have no problem following Dr. Gero's programming and just can't wait to kick that plucky saiyan's ass. Afterall, it IS Dr. Gero's hate that fuels them!

And that's just what they do. During the time #17, 18 and 16 were wandering about, the Z gang (probably ChiChi's doing) thought it would be a good idea to go to the local depaato (department store). #13, 14 and 15 find Goku in the restaurant on the top floor and shortly thereafter a fight breaks out. Eventually it moves to one of those neverending plainsland regions with Future Trunks, Vegeta and Goku facing off against the trio. A quality fight ensues until the three go super saiyan. #14 and 15 get cut down almost instantly, but #13 stays alive by absorping the generators and data chips from his fallen android brothers, transforming into the bizarre looking Super #13. The big blue Super #13 doesn't last long, though, falling to the genki dama of super saiyan Goku...which shouldn't even be possible, but you know, the DBZ movies are weird like that. :(

#16, the peaceful android
#16, like the three before him, was an android, but unlike the trio, he was not fueled by the hate of Dr. Gero. Sure, his programming made him want to destroy Goku, but it was only Goku. #16 was not a creature of malice. He appreciated nature and other living creatures, and in fact sacrificed himself for the greater good (fighting Cell, protecting #18 after her brother was absorped by Cell). He was the strongest android and followed his programming, but his peaceful personality was seen as a flaw by Dr. Gero, which was more than likely the reason he went on to create #17 and #18.

Sixteen is quite the noble character, meeting his final destruction at the hand's of Perfect Cell, which drives the young Gohan to reach super saiyan 2. Sadly, after he is destroyed by Cell, #16 is never seen again in the series. ;-;

#17 and 18, the twins

Up till this point, all of Dr. Gero's creations were androids (presumably), but Number 17 and Number 18 were his first cyborgs, made from two human test subjects. Like the others, #17 and #18 are considered failures. #17 was created first, since it is noted that too much emphasis was placed on #17's power, and he refused to follow orders. As a result #18 was created with surpressed power. Still, the cyborg twins were too tough for Dr. Gero and he was forced to implant an emergency-off switch in their bodies as a means to control them. #17 smashed the detonation device for that, though, along with Gero's head...

The twins are the only two (besides #8) to not be destroyed by the Z gang. In fact, #17 lives on to become a woodsman (interpret that as you want), and we should all be familiar with #18's fate.

#19 and 20, the final two

These are the first androids to appear in the anime after #8. #19 was a success, created to help turn Dr. Gero himself into the cyborg, #20. While they are not the androids Future Trunks foretells the coming of, it is #19 and #20, with a purpose just the same, to wreck havoc on the populace and destroy Son Goku. They are deadly, equipped with peculiar red orbs in their palms able to absorb energy through physical contact. #20 paralyzes Yamcha with this device, nearly killing him. The two are even able to absorb Goku's kamehameha technique.

Luckily for Earth, the Z fighters were prepared to meet the android menace, and we not absolutely overwhelmed by their arrival. Still, the two give the gang some trouble, absorbing the energy of not only Yamcha, but Goku, Piccolo and Vegeta. Eventually, #19 is defeated by Vegeta, and #20, previously ignorant of the power of a super saiyan, heads for his lab in desperation, activating #17 and #18.

Cell, the bio-android

"Previously, Doctor Gero tried to use bio-technology to create an android, but due to the time constraints, he programmed a computer to finish the experiment. It was created b combining the genes of Goku, Vegeta, Piccolo, Freeza, Freeza's father, and a number of other lifeforms."

Cell was the final creation of Dr. Gero, unique in the fact that he was the only "bioroid". Made from the genes of various lifeforms and raised to believe he was Gero's most perfect creation, Cell burst forth from his incubator ready to kill. He had the ability to absorb other lifeforms entirely through the syringe-like point on his tail. In fact, by absorbing #17 and #18 specifically, Cell would be able to reach his perfect form, which he did (holy crap!). Luckily for Krillin, Cell got punched so hard, he barfed #18 back up, and luckily for Earth (once again), Cell was defeated by the young half-saiyan, Gohan.

Note: Although some questionable Dragon Ball sources (chiefly Beckett and Pojo) refer to Cell as #21, he is never once called Jinzouningen #21 in the anime or manga. He is only ever referred to as Jinzouningen Cell. True, he is the twenty-first creation of Gero, but that is not his actual designation. The #21 myth is entirely fan-based.

Thus concludes the creations of the mad Doctor Gero. He appears in Dragon Ball GT, along with a few new creations, but uh, I don't really care to write about them yet.