What tension was ever in DBZ? Even death or blowing up planets were meaningless. Even the "Limits" of the Dragon Balls were constantly being broken.
You're saying this in hindsight, once the series has wrapped and we know how things go. But as each arc was unfolding, Toriyama knew how to inject tension into almost every chapter.
The Dragon Balls aren't omnipotent. We already saw with Piccolo Daimao in DB that Shenron could be killed. We also saw, with Goku after the Frieza Saga and with the Androids at the end of the Cell Saga, that if someone is strong enough, Shenron cannot affect them against their will, whether that's moving them somewhere else or altering their biology. The Dragon Balls weren't there to defeat a villain. They were there to keep one from becoming too strong or immortal, and only in a second phase were they used for "resetting" the arc's damage back to a status quo.
Arcs in DBZ have a simple layout: a villain is introduced at the beginning; by the end of it, Goku will defeat him. That's the simple premise. That's the shounen standard, used by One Piece itself.
So tension comes from altering everything
in-between those stages. Stakes are built on our fear, as the reader, that characters might lose something or someone before Goku dispatches with the villain.
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Raditz comes, fights Goku and Piccolo, and dies taking Goku with him.
The deus ex machina of the Dragon Balls will bring Goku back to life. But it's that very safety net that attracts Vegeta and Nappa to Earth, two threats way bigger than Raditz was on his own.
Goku trains in the Afterlife and rushes back to deal with the Saiyans. You know from the arc formula that he will defeat them once he gets there.
So tension is injected
before that.
By the time Goku makes it to Earth, Tien and Chiaotzu have died. It's Chiaotzu's second death at that, so he won't be brought back. Not only that, but even if he could be brought back a second time--Piccolo has also been killed, and with him the Dragon Balls are gone.
We're 1/2 into the arc and the deus ex machina is already out of the picture.
Then Goku arrives, dispatches of Nappa, beats Vegeta's ass.
But Vegeta has an ace up his sleeve. Even with Kaioken Goku still can't win against his Ape form.
It's only thanks to Gohan, Krilin, and Yajirobei that the planet is saved--and here already Toriyama is tweaking his formula.
Next arc, you know that once Goku arrives on Namek he will fight
and defeat Frieza.
That's set in stone.
So Toriyama plays with tension by having weakling duo Gohan and Krilin be the main protagonists, both running away from Frieza's overwhelming forces, and trying to navigate around Vegeta's backstabbing nature.
And when Goku finally lands on Namek?
Gohan is paralyzed. Krilin is about to be killed. And even after taking care of the Ginyu squad, Goku still needs more recovery.
Then comes Frieza. Everything they throw at him doesn't phase him. His transformations seem endless and any technique the DBZ fighters use is meaningless. Even the genkidama isn't enough. Piccolo almost dies. Vegeta dies. And then Krilin dies.
And it's his second death at that--so he won't be back.
That's what pushes Goku to turn Super Saiyan.
And even after the transformation, the story doesn't play it safe. The tension keeps rising, with Namek's imminent explosion and Goku's search for a spaceship to leave the planet in time.
Next arc.
Goku is away. Frieza, who's been shown to be nigh unstoppable, appears on Earth. Not only that, but there's TWO of them. And Vegeta, who's the strongest character on the protagonist's side around, knows that he can't handle them.
Again: we know that once Goku makes it to Earth, he will manhandle Frieza. But what will the price of his tardiness be? What will Frieza destroy, who will he kill?
That's rising tension over and over in just two chapters.
Then a stranger appears out of nowhere and with ease kills both Frieza and his dad.
Not only that, but this stranger comes from the future and informs them of higher threats than Frieza himself, threats who have killed everybody in the future.
The DBZ fighters train for two years:
and still Yamcha dies
and still Goku is defeated by #20 and almost dies to the heart disease
and still Gero gets away.
And as if that wasn't enough?
Trunks tells them that these
weren't the androids he warned them about.
And
then Trunks finds someone else who's come back from the future.
And that his future self has been killed by this someone.
And a weird bug monster starts sucking up lifeforms left and right, creeping out even Kami.
Stakes are introduced within this new web of characters, with the fate of the planet (and the very galaxy) being in the background, while the foreground focuses on the interpersonal and the psychological. Cell becomes perfect because of Krilin's heart. Cell becomes perfect because of Vegeta's pride. Each of those variables adds uncertainty in the reader, because the characters aren't acting according to plot, but according to their own characterization, which can lead to unexpected developments.
Even in the last act of the arc, when things revert to the familiar martial tournament, a format that lets us know that Goku will fight and defeat Cell by the end of it, Toriyama still shakes things around.
Goku gives up.
There's tension as Gohan tries to live up to the expectations.
There's tension as Goku realizes his own misreading of Gohan's character, and has to die for it.
There's tension as Cell returns even stronger than before, and begins killing every DBZ fighter left.
It's not the Dragon Balls that save the day. They aren't the undo button to cancel the arc's consequences. They merely restore the planet, but don't wipe away the relationship changes generated by the Androids' plot.
Goku is still gone.
Gohan is still expected to be more than he can be.
#18 is still treated as a person and not a machine.
The arc has provided growth that doesn't get waved away.
Even the Buu Saga, which starts with a lighter tone, and where stakes don't really become tangible until Vegeta kills himself, tension rises beyond previous limits.
Blowing up planets is meaningless? Here's a character who can erase entire galaxies at once.
Death is meaningless? Here's a character who comes to the Afterlife, who scares the gods themselves, and who threatens to erase a soul once and for all--no do-over, no resurrection. A character who's never been defeated, merely sealed away.
That is the apex of stakes in the DBZ universe. You can't go much higher than this: that's why the sequels had to introduce multiverses and more separate future timelines.
Buu is the be-all and end-all, and from Oolong's introduction to Buu's demise, Toriyama constantly ups the ante and tweaks what characters care about, what they can lose, what they
have to lose in order for the story to still generate emotional investment.
And Naruto never had any Stakes. Even things like not being able to Use the Wind Rasengan-Shuriken because it was too damaging to Naruto was gone by the next arc with a new power up. So what stakes were there?
Like I said, Naruto is even better at creating tension and setting up stakes because it doesn't follow the same shounen baseline of "this arc's villain will be defeated by Naruto by the end of it". That already generates uncertainty in the reader. Aside from it, half of the premise is about Naruto proving himself to the village (and thus being chosen as their hokage) and the other half is him saving his "best friend" from a downward spiral of revenge and hatred.
The Sasuke-Naruto bromance is the main engine of tension of the story. That's why the highest point of engagement is with their fight at the Valley of the End, where Naruto fails to defeat or convince Sasuke.
The first half of the story is masterfully built on cause-and-effect, on unescapable choices that leave a mark on the characters for the rest of the series.
If Naruto wants to be ninja, he will have to stop, even kill, tragic people like Zabuza and Haku.
If Sasuke wants power, he will have to subjugate himself to monsters like Orochimaru.
If Naruto wants to save Sasuke, he will have to give up control to the kyuubi.
If Naruto wants to be a good hokage, he will have to not make Gaara's own mistakes and let grief consume him.
That's why I said that Nagato shat the bed.
Up until the end of the Pain Arc, Naruto the manga has flawless execution of pay-and-reward. Characters go through trials, pay a heavy price, and come out changed for the better or the worse. Nagato's undoing the Leaf destruction takes away part of the good faith the audience has in the author to deliver on set-ups and payoffs without cheating.
From the Pain Arc onward, the reader becomes like you, Dettles: he starts asking what's the point of all the new conflicts if everything can be handwaved away with a single technique. Naruto remained the same in that arc. The Leaf remained the same. (Sure, Naruto couldn't become the leader of the Leaf if there is no Leaf, but Kishimoto wrote himself in that corner.) Only Nagato was changed by it--and he dies.
At least Jiraya wasn't brought back.
By the Ninja War, no matter what stake Kishimoto introduces, it's no longer credible because there is this precedent that the slate will be wiped clean. The whole ninja alliance gets godly chakra from Kurama outta nowhere? And dumb Neji still dies? No wonder it felt unreal to many, expecting to see him brought back to life by some Rinnegan bullshit.
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One Piece follows the DB formula: by the end of the arc, Luffy will have defeated the villain. That's a given. Tension is built before that, focusing on what the characters may lose, in terms of material possessions, relationships, or health,
before that point.
You don't feel tension in Drum Island because Wapol is strong: far from it. You feel tension because of Chopper and Hiluluk's relationship. You feel tension because Wapol wants to erase Hiluluk's flag. You feel tension because Wapol has stripped the country of doctors in the one arc where Nami is sick and Sanji is bleeding and Luffy is about to die from hypothermia.
Alabasta is the first arc where Oda goes all-out on stakes. We've been with Vivi for four storylines now, we care for her, we want to see her and her people free. The Strawhats care for her. Hell, we get one of the series' most iconic images, with the Xs on each member's arm, thanks to Vivi.
We slowly learn about Baroque Works' plan.
We learn about Croc's identity.
We're captured alongside Smoker.
We see all the agents who need to be defeated in order to stop Croc's plan.
We even see Luffy be defeated over and over.
And once he finally succeeds?
Croc still has a backup plan and a timebomb will kill most of the population.
And Pell has to sacrifice himself to stop it.
(Which gets undone and leaves a sour taste in many readers' mouths, but everything up to that epilogue is done perfectly).
Enel's destruction of the Upper Yard follows the same pattern on an even larger scale.
In Water 7, Oda mines the crew itself for stakes:
the Merry is being abandoned
Luffy and Usopp have a falling out
Robin leaves the crew.
It all happens so quickly, the reader is thrown for a loop. For the first time in the series, the future of the crew is unknown.
And this is only the setup of the arc.
Luffy and Zoro get easily defeated. Sanji goes on a solo mission to rescue Robin; rescues Franky, is helped by Usopp, and almost succeeds in getting Robin back, before things escalate again.
Even once Robin is back with the crew, at the climax of the arc, and Usopp has to infuse Luffy with a healthy dose of willpower, stakes are still being raised with Lucci promising to go apeshit on Luffy's crewmates, with the Buster Call being called by mistake, with the SHs being surrounded on all sides and with apparently no way out.
You can call the Merry's last-minute arrival an asspull, but it worked magnificiently in conveying the arc's message ("We're crewmates to the very end."). That's an arc with repercussions for the series as whole. The arc that rounded Robin's character, that introduced Usopp's persona (before Usopp as a whole was abandoned), the arc that redefined the relationships between captain, vice captain, and potential crewmates.
Water 7 is the perfect OP arc in terms of stakes, which is why Oda replicates it again with Ace.
The crew is defeated on Sabaody. Every SH is on their own. Anything can happen. As if that weren't enough, Luffy's brother is being scheduled for an execution.
Cue Impel Down: by the end of the arc, we know that Luffy will succeed in breaking his brother out of the prison.
Or not.
He was too late, and now Ace's been taken to Marineford.
So to Marineford we go.
By the end of the arc, we know that Luffy wil succeed in saving Ace from being executed.
Or not...
Misery and misery, defeat after defeat. That's what makes this stretch of the story so rewarding. Oda sets up obstacles; whenever Luffy fails to clear them, a heavy price is paid.
Oda tried once more to replicate the structure in WCI, but by then the overall writing had become much weaker than it was pre-timeskip.
In FMI he could only inject tension through the overused timebomb plot that was the Noah Arc, and by having Luffy bleed out for narrative purposes.
In PH people constantly run around just to run around. There's nothing at stake, not even with Caesar demonstrating his WMD.
DR has another timebomb, and an entire island of people cheering live on Luffy to win against the villain. There is no secret scheme, no backup plan. Nothing that could surprise us or the characters. The SHs defeat their opponents. Luffy defeats Doffly. Cut and clean.
WCI has a healthy dose of tension thanks to Katakuri and even to Pedro's kamikaze ploy. Things are again dire, we see a Yonko's fleet posing a real problem... up to the point where a crazed all-out BM lands on the Sunny... and nothing happens. Nobody is injured, nothing is irredeamably damaged. No everlasting consequence on the story as a whole. Wadatsumi pukes out a Sunny decoy to fool the BMP; the Sunny makes away without a scratch. The end of the stakes.
Then comes Wano.
The SHs enter a country that cannot be entered--and pay no price.
The SHs and the Scabbards are allowed to travel openly and to conspire against the government--and pay no price.
Kaido meets Tama--and pays no price.
Momo is magically aged up to be able to control his faulty fake DF (which turns out to not be faulty at all)--and pays no price for the sudden power boost, not even a little panel of him commiserating his wasted youth.
Even when the villain does something useful, like capturing and executing Yasue, the event is still turned in the protagonists' favor.
Luffy is imprisoned? Free training.
The Scabbards had a traitor? Well, so did Orochi's court.
At every step of the story, everything that could work in the SHs' favor does. They lose nothing, they are surprised by nothing. Even the ice zombie virus is merely a sideplot to keep Chopper occupied. There is an easy counter to Kanjuro's fire demon. The villain's daughter is fighting for the good guys. The eight-headed dragon serpent is defeated by easily cutting off his head. BM goes retarded and helps the SHs, before getting more retarded and falling to Kid and Law. Why were so many readers expecting the raid to fail? I couldn't tell--this is such a compelling story filled with ups and downs.
Even when the arc hits its lowest low, narratively speaking, and the WG sabotages Luffy so that Kaido can kill him... surprise, motherfucking giant infodumping elephant is here to let us know that god is back. And there emerges Nika, fully stretching the stakes down to hell.
In Egghead, you have:
1. the fastest Admiral on earth;
2. a demon capable of popping up heads with his gaze;
3. CP0's best assassins, two of which awakened zoans;
4. the WG's strongest engineered unit.
And still the SHs never lose anything, aren't even injured in any meaningful way, and the only ones who die are
clones of the one guy who realized he'd made a mistake of creating those clones in the first place.
Now Elbaf is giving up the King of the World, the devil himself, who can't even hurt a little child. Luffy gets impaled twice while the SHs are working the hairdryer on a frozen chick, and Zoro and Sanji exchange one-liners with their opponents in no rush to finish the fights. Even Aokiji's entrance at the end of the Long Ring Long Land arc generated more apprehension in the crew.
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Bleach starts strong: having the Soul Society arc revolve around Rukia's execution helps gradually raise the stakes. Having Ichigo fail to stop the plan, and revealing the mastermind behind it,
and having him get what he was after all along? Perfectly executed escalation. And we get drawned-out fights for most of the arc.
Then Kubo repeats the same plot with Orihime in Hueco Mundo. And we get drawned-out fights for most of the arc.
Then a whole human city is substituted with a fake one to avoid senseless distruction, taking away from the stakes that a massive war within a human settlement could generate. And we get drawned-out fights for most of the arc.
Then a villain appears with the power to rewrite anybody's past and make himself their friends and most trusted person at will--and Kubo does fuck all with it, when that's the sort of paranoia-fueling power that could hold an entire series on its back.
Supreme God Yacht Boat dude is more of the same, and the last arc is nothing but "who can make the enemy think they're hit while preparing a secret from-behind counter-hit" for chapters and chapters at a time.