Why did Gero use humans for androids 17 and 18?

[MetalMadness]

While watching the new Kai dub, 17 asks 16 if he was a human, and 16 replies that he is purely mechanical, and then 17 wonders if Gero was capable of building completely mechanical androids, why did he use humans for himself and 18?

And then I wondered the same thing, why did Dr Gero use humans for 17 and 18 when it was already proven he could build purely mechanical androids? Is it ever said in the anime why?

[Booney]

Well, they were created for Cells perfection weren't they?

So my guess is Cell can't absorb machines and is only compatible with biological, erm...stuff.

[rereboy]

All of the androids that Gero created until #16 were failures in Gero's eyes.

Then, #16 was also a failure, probably because of his good nature.

So, Gero tried a different approach and developed #17 and #18 from living human bases.

But they were also failures... They were too defiant...

So, he then once again changed his approach and went back to purely mechanical, but changed the energy system and other things...

And so, finally, he created an android that he deemed a success: #19. He wasn't as powerful as some of the previous ones, but he was perfectly obedient and had the same tastes of destruction and torture that Gero had and he was way more powerful than he needed to be to take over the world and defeat Goku and his pals (or so he believed).

[Bussani]

Supposedly, #17 and #18 weren't even the first human-based Androids. #8 is said to have a human base in the Daizenshuu, so it's not unprecedented. If he could do both, why not try both?

It is possible he used human bases for them because he planned for them to get absorbed by Cell. On the other hand, I wonder if it was really Gero who planned for that, or if it was the idea of the computer that built Cell. Maybe it went, "Hey, Gero built these two human based Androids. I calculate that if this Cell thing adds them to itself, it will become even greater!"

[TheDevilsCorpse]

It is possible he used human bases for them because he planned for them to get absorbed by Cell. On the other hand, I wonder if it was really Gero who planned for that, or if it was the idea of the computer that built Cell. Maybe it went, "Hey, Gero built these two human based Androids. I calculate that if this Cell thing adds them to itself, it will become even greater!"

I do believe 17's Daizenshuu 7 bio states that the twins original purpose was to allow Cell to evolve,...

[Herms]

It is possible he used human bases for them because he planned for them to get absorbed by Cell. On the other hand, I wonder if it was really Gero who planned for that, or if it was the idea of the computer that built Cell. Maybe it went, "Hey, Gero built these two human based Androids. I calculate that if this Cell thing adds them to itself, it will become even greater!"

I've always wondered what exactly it is Cell needs from them to reach his perfect form. The most logical assumption (to me at least) would be that it's their infinite energy generators, since that's where the two of them get their power from in the first place. But then, after becoming complete Cell doesn't really seem to have infinite stamina the same way 17 and 18 do. And if those engines generate infinite energy, why would you really need two of them? I can understand keeping one as a spare, but it seems odd that adding another infinite energy engine into the mix would create the huge difference we see between Cell's second and final forms. But then if it's not the engines Cell needs, what they heck else do those two have that he couldn't get from anyone else in existence?

My made-up theory is that it is the engines Cell needs, and the reason Cell needs two is because while 17 and 18 are able to derive infinite, never-fading power from those engines, it's only power of their level. That is, they've got an infinite supply of X-level power, but they can't go beyond that, no matter what. They'll never get tired, but there's no way they could generate the sort of power 16 or Super Vegeta can. Cell is able to take those engines and use them at a level beyond what 17 and 18 can, which is why he can generate power so much greater than 16 or Super Vegeta, but when the engines are used at that level they can no longer act as sources of infinite power. It's like if I'm walking along at a pretty slow pace, I can walk like that basically forever (eh, give or take), but if I start trying to run at 10 miles an hour I'll tire out pretty soon. So that's why perfect Cell needs senzu to refresh himself, despite running on the same engines that gave 17 and 18 infinite stamina. And he needs two because...uh, well I guess it still doesn't explain that specifically, but under this setup you can at least see why two would be advantageous, as opposed to if we assume that "infinite energy" holds true under all circumstances.

]I do believe 17's Daizenshuu 7 bio states that the twins original purpose was to allow Cell to evolve,...

Yeah. Makes me wonder if 17 and 18's whole purpose was to just to put the infinite energy engines into a form that Cell could merge with. 16 is supposed to have an infinite energy engine too, but as we see Cell can't absorb him. So maybe it just wouldn't work to install Cell with the engines directly, for some reason they had to be built into humans who Cell could absorb. So 17 and 18 are just like glorified Super Game Boy adapters.

[Fox666]

I've always wondered what exactly it is Cell needs from them to reach his perfect form. The most logical assumption (to me at least) would be that it's their infinite energy generators, since that's where the two of them get their power from in the first place. But then, after becoming complete Cell doesn't really seem to have infinite stamina the same way 17 and 18 do. And if those engines generate infinite energy, why would you really need two of them? I can understand keeping one as a spare, but it seems odd that adding another infinite energy engine into the mix would create the huge difference we see between Cell's second and final forms. But then if it's not the engines Cell needs, what they heck else do those two have that he couldn't get from anyone else in existence?

My made-up theory is that it is the engines Cell needs, and the reason Cell needs two is because while 17 and 18 are able to derive infinite, never-fading power from those engines, it's only power of their level. That is, they've got an infinite supply of X-level power, but they can't go beyond that, no matter what. They'll never get tired, but there's no way they could generate the sort of power 16 or Super Vegeta can. Cell is able to take those engines and use them at a level beyond what 17 and 18 can, which is why he can generate power so much greater than 16 or Super Vegeta, but when the engines are used at that level they can no longer act as sources of infinite power. It's like if I'm walking along at a pretty slow pace, I can walk like that basically forever (eh, give or take), but if I start trying to run at 10 miles an hour I'll tire out pretty soon. So that's why perfect Cell needs senzu to refresh himself, despite running on the same engines that gave 17 and 18 infinite stamina. And he needs two because...uh, well I guess it still doesn't explain that specifically, but under this setup you can at least see why two would be advantageous, as opposed to if we assume that "infinite energy" holds true under all circumstances.

That's too complicated.

Essentially, Cell cannot absorb non-biological beings, and no.17 and 18 were created so that he could reach his perfect form. There are specific components on no.17 and 18 bodies which Cell needs to reach a new form.

You will only get frustrated if you try to understand it in some kind scientific way. I guess it's better to look at it as a fusion, instead of something completely logical.

[rereboy]

Cell doesn't need #17 and #18 to be complete. This is proven in the manga by the simple fact that Cell reached his perfect state once again with a zenkai and without having #18 in him.

However, it is extremely hard for him to reach his perfect state without them. He could probably absorb the entire population of Earth and not even reach his semi-perfect state, and he probably didn't even know he had the ability to have near death power ups, since he was pretty surprised when it happened.

The computer probably told him that the only sure way of becoming perfect was to absorb #17 and #18, which is why he went to so much trouble to do so.

[Ranmarotto]

He might have used humans as a base because that was all he could work with at the time. Remember, 17 and 18 were both built before he created 16, so he may have discovered new methods of creating artificial humans in that time.

[Piccolo Daimao]

Cell doesn't need #17 and #18 to be complete. This is proven in the manga by the simple fact that Cell reached his perfect state once again with a zenkai and without having #18 in him.

However, it is extremely hard for him to reach his perfect state without them. He could probably absorb the entire population of Earth and not even reach his semi-perfect state, and he probably didn't even know he had the ability to have near death power ups, since he was pretty surprised when it happened.

The computer probably told him that the only sure way of becoming perfect was to absorb #17 and #18, which is why he went to so much trouble to do so.

I always thought that Cell did need #17 and #18 to be complete, like they were part of his evolution. I don't think that simply absorbing humans would cause him to transform into his Perfect form. Perhaps, if he absorbed enough humans, they would grant him enough power and speed to match his Perfect form, but not with everything else that came with his evolution via absorbing #17 and #18.

Chapter: 380 (DBZ 186), P2.4
Context: when asked if his perfect form could beat Vegeta
Cell: “Power! Speed! Technique! Brains! Mental Strength! I will be perfect in every way! That’s what the computer told me!!”

Basically, Cell would be able to reach the power and speed of his Perfect form, but he wouldn't change in appearance, technique, brains and mental strength. And even then, I doubt he'd be able to reach the full power he used against SSj2 Gohan. I think he'd only be able to reach the level he fought Super Vegeta and SSjG3 Trunks at, because I think absorbing humans could only take him so far, and actually becoming Perfect would push him past that and evolve him to the level that he could actually reach the full power he fought SSj2 Gohan with.

As for Cell reaching his Perfect form without #18, I think we all know that it was for plot reasons. You know, build up drama and suspense (which would defeat its purpose if Cell came back in his visibly weak semi-perfect state and injured Gohan; we've associated Cell's Perfect form appearance with the power he had). My theory is that regenerating from his own self-destruction from only his nucleus was unnatural for his body, so Cell, rather than remaining in his semi-perfect form, "rebooted", almost, back up to his Perfect form, which Cell admitted himself that he was surprised by (which supports the "unnatural" thing; Cell logically should know everything about his body, since the computer created him and told him everything about him). It's a nonsensical thing to happen, but it's just like Cell gaining a Zenkai from his own self-destruction (self-destruction would mean "death", but Cell kind of came back from death with his regeneration, also unnatural, and all the way back in the Freeza arc, Vegeta said that there'd be no effect if he tried to kill himself, which is why he got Kuririn to half-kill him) or somehow obtaining his teleportation (wasn't there a theory that Cell gained some of Goku's cells or whatever during the explosion that killed them both?).

For reference, here's some of the statements that I talked about.

Chapter: 413 (DBZ 219), P10.1, P11.3-4, P12.1
Context: after regenerating from his self-destruction
Cell: “There’s a small clump inside my head…This makes up my nucleus…As long as that clump isn’t destroyed, my body can continue regenerating…When I self-destructed, my nucleus fortunately remained uninjured…Quite frankly, I hadn’t calculated on being able to regenerate…I was lucky…And even more happily, my body regenerated as my perfect form, even without No.18…And it wasn’t merely my perfect form: I had vastly powered up like Son Gohan…This was probably done by the Saiyan cells, which greatly increase in power when they are saved from the brink of death…And I even managed to learn Son Goku’s Teleportation…So in short, I was able to return here, having become even more perfect. It seems that rather than defeat me, Son Goku has given me several presents.”

Chapter: 303 (DBZ 109), P11.1-2
Vegeta: “Alright?! Do you get it?! How when we Saiyans revive from the brink of death, our strength increases! So go ahead and half kill me! There’s no effect if I try to kill myself! You do it! Quickly! Freeza is about to perform his final transformation!”
Kuririn: “I-I could half-kill you with my power…”
Vegeta: “Don’t worry…I’ll lower my battle power to its limit…! It’s fortunate that the Namekian brat who can instantly heal people is here…”

17 and 18 were both built before he created 16

Were they? Not meaning to be snarky or anything, but doesn't the number 16 come before 17 and 18?

[rereboy]

Regardless of all that, Cell reached his perfect state, and became even stronger than he was the last time he reached it, without #18 in his body.

So... That pretty much implies that he doesn't actually need them.

[TheDevilsCorpse]

without #18 in his body.

And 17, since he was killed when Cell self-destructed.

[rereboy]

Hmm, not sure about that... Shouldn't #18 be destroyed or harmed when Vegeta's Final Flash destroyed the right part of Cell's body? Or when Goku destroyed his upper body with his Kamehameha?

[TheDevilsCorpse]

Hmm, not sure about that... Shouldn't #18 be destroyed or harmed when Vegeta's Final Flash destroyed the right part of Cell's body? Or when Goku destroyed his upper body with his Kamehameha?

No, because its Toriyama. 18 is shown to come out of Cell at full size, unharmed, after taking Vegeta's Final Flash and Goku's Shunkan-ido Kamehameha, so the Jinzoningen are obviously kept inside Cell in some magical manner the likes we wouldn't see again till Buu. xD But 17 is resurrected with the wish to revive all those killed by Cell, since he is blatantly seen in the Buu Arc. The only time Cell could have possibly killed him is when he self-destructed, because 18 was shown to survive the absorption process.

[rereboy]

That really was one hell of a zenkai then

[Bussani]

I always thought Cell's body remembered the perfect form and regenerated into it even without the Android(s). It sort of makes sense in a way; even if you change someone's DNA, they won't instantly transform like in the movies. The old cells need to be replaced by the new ones, which takes time. Cell's body had to rebuild itself from scratch, so it was the perfect time to create the form without the Androids.

[hleV]

I believe creating a fully-mechanical android was a pain and needed a well-programmed AI. Gero used normal humans so he would only need to enhance their capabilities and alter their mindset instead of creating everything from scratch.

[BlazingFiddlesticks]

I can't imagine a practical reason to actually use humans in and off themselves.

But, in keeping with the tradition of executive meddling becoming ingenious plot twists in the Cell arc, the fact that Cell could absorb them due to their being biological must have made him that much easier for Gero to develop ("17 and 18 are useless to me, but aren't going to die unless I deactivate them, so they can be a cheap power-up"), thus increasing his plausibility somewhat while also cleaning up the fate of the siblings.