Dragon Ball Z (1989–1996)
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This title page (Dragon Ball Z: Doragon bôru zetto (1989)) is for the original Japanese release of the anime Dragon Ball Z, as it was broadcasted on Fuji TV in Japan, uncut. The other title page (Dragon Ball Z (1996)) is for the English dubbed version, that was broadcasted in North America, with several changes and cuts in it's original broadcasting. Edit
The English Cast listed here, was approved by IMDb Staff after reviewing carefully the special case of the 2007 release of the new dub, with a script more faithful to the original japanese, of the 291 "uncut" episodes of the FUNimation "Dragon Boxes". This cast is not listed by number, and the idea is to reflect the differences between the original USA dub broadcasted on TV and the new version only available for sale on DVD. Edit
Some says that Akira Toriyama forgot to draw them with tails in the manga (no reference found of this statement made by the author himself).
It's possible the two kids were born with tails but got cut off as soon as they were born.
The most accepted possibility, discussed by fans all over the world for years, is that because Gokû and Vegeta impregnated their respective wives after their tails were gone for good, and achieved the Super Saiyajin state, they passed along different genes than Gokû passed to his eldest son, Gohan (who WAS born with a tail.) Edit
Akira Toriyama initially never had any plans to make Vegeta a major character (he had initially planned to end the series after Goku's fight with Freeza). When things changed and he ended up making Vegeta a major player in the events that ensued, he started making the character taller. There's no "in-series" explanation for this, Toriyama just started drawing him taller (closer to Goku's height) when it was established he would be a major character. Edit
It's true that they knew Gohan in Dead Zone, however Dead Zone was a movie created by Toei Animation. The movies are "side-stories", and (with rare exceptions) could never fit into the actual series timeline. Akira Toriyama did not directly create the movies (he only had minor involvement), thus they often contain plot holes that contradict things that take place in the series, and in Toriyama's original manga. As a general rule, the theatrically-released movies are not canon. The TV specials, on the other hand, DO fit into the series timeline, though even they have a few minor contradictions and plot holes.
So, long story short, they don't know Gohan because they've never met him before, since Dead Zone (like any other theatrical movie) isn't canon. Edit
Yes. The new version was called Dragon Ball Kai (Dragon Ball Z Kai in America.) It is essentially a new version of the show that cuts out the majority of the filler segments. In Japan it ran from 2009-2011, for 98 episodes - however it ended its run at the conclusion of the Cell Saga.
The show is not redrawn, though certain parts of it are, most likely to remove damaged frames/scenes/etc. It was released on both DVD and Blu-Ray, however it was edited from the original Dragon Ball Z animation (some nudity and violence has been removed.) In USA it airs on the Nicktoons network, although TV versions are even more edited than the home video "uncut" releases.
In Japan, Dragon Ball Kai was picked again to continue into the Buu saga, when the new series Dragon Ball Cho: Dragon Ball Super was announced. Edit
Not at all!! Neither!!
Tao Pai Pai was a hired assassin employed by the Red Ribbon Army, and not actually someone within their ranks. This confussion happened only in the English version: the name "General Tao" is a dubbing error (this stems from the Mystical Adventure movie in which he WAS a General, but that movie is non-canon), and indeed, later dubbing material like the FUNimation dub of the original Dragon Ball call him "Mercenary Tao." The original Japanese anime never made such a mistake, nor the dubbings made straight from japanese (like the Mexican dubb, used in all Latinamerica).
Commander Red was the leader of the Red Ribbon Army. In fact, Dr. Gero never appears once in the first Dragon Ball anime. Obviously Toriyama hadn't even invented Gero at the time he was doing the original Dragon Ball, so you might say he was a "behind the scenes" character that simply invented things for the army. He was certainly not in any sort of leadership position. Edit
Dragon Ball consists of 153 episodes, 3 movies, and 1 tenth-anniversary movie.
Dragon Ball Z consists of 291 episodes, 13 movies, 2 television specials, 1 "lost movie" comprised of footage from an obscure FMV game, and a 20th anniversary movie.
Dragon Ball GT consists of 64 episodes and 1 television special.
Dragon Ball Kai consists of 98 episodes by the time of Cell Saga.
Dragon Ball Super is currently airing and the total number of episodes is still unknown. Edit
The anime is paced far slower than the manga, and features a number of "filler" episodes and one entire filler "Saga", that weren't in the original manga. These had to be added into the anime to keep pace with the release of the manga, which was still being put out as the anime was being made. As these fillers were created with only minimal involvement with Akira Toriyama, they often contradict major plot points of the series. For instance, the entire Garlic Jr. Saga was a creation of Toei Animation, and does not appear at all in Toriyama's manga. Some filler segments are merely fights from the manga that are extended, as well as drawn-out extended scenes of characters powering up. Amusingly, most of the complaints people have about the show stem from anime-only filler and aren't problems that exist in the original manga. Edit
Japanese anime like Dragon Ball Z, is not divided in "Seasons" during it's broadcasting. There is only 1 Season with 291 Episodes for the original Japanese broadcasting.
However, the series is usually divided in "Sagas".
For USA viewers, there's no simple answer to this question, since the seasons that aired on USA TV are not the same as the ones that were released in the DVD season sets.
If you're going by the seasons that aired on USA TV, there are 7.
1 - Saiyan Saga. 2 - Namek Saga. 3 - Captain Ginyu Saga, Frieza Saga. The Garlic Jr. Saga aired on Cartoon Network as a "mini-series" between Season 3 and 4. 4 - Trunks Saga, Android Saga, All Cell Sagas. 5 - Buu Saga Part 1. 6 - Buu Saga Part 2. 7 - Buu Saga Part 3.
The season sets released on DVD use a different format, and there are 9 of them total.
1 - Saiyan Saga (with beginning of Invisible Spaceship stuff). 2 - Namek and Ginyu Saga. 3 - Frieza Saga 4 - Garlic Jr. Saga, Trunks Saga, Android Saga. 5 - Imperfect Cell Saga, Perfect Cell Saga. 6 - Cell Games Saga. 7- Afterlife Tournament, World Tournament. 8 - Babidi, Buu. 9 - Fusion/Kid Buu/Epilogue. Edit
Goku left his Power Pole at Kami's Lookout in Dragon Ball. It serves as an elevator up to Kami's Lookout from Master Karin's Tower. Though he does use it in the Dead Zone movie, and Gohan uses it in the World's Strongest movie (though this is one of the many movie plot holes, it should be at the Kami/Karin Tower Link.) Indeed, other Z-Fighters later train at the lookout, so they would (most likely) need the pole there to be able to reach Kami's place.
Why Goku stops using Kinton is never really given an explanation, and it does, indeed, show up in the first beginning of Dragon Ball Z. The most likely answer is because it became obsolete to Goku, since he learns the bukujutsu (flying technique). In later sagas he can fly far faster than the cloud could ever carry him, and he eventually learns the Shunkanido ("Instant Transmission technique" in some dubbs), which is a far more efficient form of transportation.
Later we see that Goten uses the Kinton Cloud when Gohan first started High School. Edit
The drivers license episode was anime-only filler. There's also no mention made of why she doesn't use the Kinton Cloud to go to the store and get groceries; by this time in the series Goku isn't using it anymore, and it's been established in the past that she could ride it. One possible explanation is she is no longer pure at heart, as seen when adult Goku carry her on his arms while flying on Kinton. Edit
A few things.
The "lost movie" The Plan to Eradicate the Saiyans, was never released in any form in USA. This is because it is based on an obscure Japan-only video game. However, a remade HD version (which features some differences from the original) is now available on the Raging Blast 2 video game.
The 20th Anniversary Movie - Yo! Son Goku and His Friends Return! has never been released in USA either. There was a promo only Japanese home video release, but no word on an USA release yet.
There are also two "lost episodes" of the original Dragon Ball, which include a traffic safety one, and a fire safety one.
There are some "specials" in which what has happened in the series/movies/etc. is described, however these are Japanese only, and are even obscure over there.
The Episode of Bardock special is not available in USA yet.
As this is the JAPANESE title page of the Dragon Ball Z series, it will be updated with all the japanese episodes. The two TV-Specials are NOT episodes of Dragon Ball Z, so they has their own title pages on IMDb as TV Movies. Edit
By far the most frequently-asked question on the message boards about the show.
At this point, Gohan has received his Mystic powerup from Rô Kaiô Shin. While it doesn't look like he is in an advanced state, after receiving his Mystic powerup he is just as strong, if not stronger, than a Super Saiya-jin 3.
Transforming into a Super Saiya-jin (considering it is even possible in this state) would most likely only waste energy. It might even be a downgrade (some of the Budokai video games treat "Mystic" as a transformation on its own, above Super Saiya-jin 2 for instance.)
So long story short, he doesn't transform because his abilities have been unlocked by Rô Kaiô Shini, and he's as strong (if not stronger) than a Super Saiya-jin 3. Transforming, if possible, would only waste energy or even be a downgrade in strength. Gohan's downfall and subsequent absorption by Super Buu could be attributed to his increased cockiness when fighting in Mystic state. Edit
Numerous Dragon Ball/Z/GT movies/specials/etc. have been released over the years. Here is a brief overview of each, USA/English versions:
-Curse of the Blood Rubies: Retelling of how Goku met Bulma and several of his other friends. A little girl enlists their help to rid their land of a gluttonous king.
-Sleeping Princess in Devil's Castle: Retelling of how Goku first met Krillin and how they came to be Roshi's students. The gang journeys to a haunted land to rescue Bulma from a variety of monsters.
-Mystical Adventure: Roshi takes Goku and Krillin to fight in a martial arts tournament in a distant land - but quickly find out not all is right in the kingdom they arrive in.
-Dead Zone: Set a year before Dragon Ball Z begins, a demon whose father competed for the role of Kami and lost seeks out revenge against those responsible - and aims to use the Dragon Balls to make himself immortal.
-The World's Strongest: 50 years ago, a mad scientist's lab was covered in ice not even the strongest attacks can melt. Using the Dragon Balls, his assistant frees him and his lab, and he begins seeking the world's strongest body to use for his own.
-The Tree of Might: Aliens arrive on Earth, planting a mysterious tree that will suck the life out of the planet. Their leader is a Saiyan with an all-too-familiar look about him....
-Bardock: The Father of Goku: Set 20 years before Dragon Ball begins, this feature tells the story of Goku's father, who led a brave last stand against Frieza and his forces.
-Lord Slug: A long-exiled evil Namekian comes to Earth, looking to make a base out of the planet. Goku and his friends set out to prevent their plans from coming to fruition.
-Cooler's Revenge: Frieza's brother Cooler arrives on Earth, seeking revenge for the death of his brother at the hands of a Saiyan.
-The Return of Cooler: Cooler survived his previous battle with the Z-Fighters, and has combined with a growing cybernetic colony. Using his limitless regeneration techniques, he unleashes threat after threat against the Z-Fighters, who have arrived on New Namek to rescue the world from his wrath.
-The History of Trunks: The tale of Future Trunks and his doomed timeline, before he came back to the present.
-Super Android 13: Three forgotten androids created by Dr. Gero arrive in the city, looking to hunt down and destroy Goku. But Goku and company have no intention of just allowing themselves to be destroyed.
-Broly: The Legendary Super Saiyan: Vegeta gets a mysterious invitation from a surviving Saiyan to rule over a new Planet Vegeta. He and the other Z-Fighters go to check it out, but quickly discover this Saiyan holds a grudge against King Vegeta... and that his son is something else altogether.
-Bojack Unbound: A martial arts tournament on Earth goes horribly awry when space pirates invade and begin battling the Z-Fighters. With Goku dead, though, it won't be an easy win!
-Broly: Second Coming: Broly arrives back on Earth, looking to get revenge on the no-longer-alive Goku for his defeat. Will the next generation of Z-Fighters stand a chance?
-The Plan To Eradicate The Saiyans: A Tuffle scientist is plotting against the surviving Saiyans, finding ways to revive old villains to battle the Z-Fighters.
-Bio-Broly: Broly is dead, but a mysterious group has created a biological clone of the Legendary Super Saiyan. It's up to Goten, Trunks, and Android 18 to deal with this newfound threat.
-Fusion Reborn: An accident in otherworld has resulted in the creation of a mindless, destructive villain. As if that wasn't bad enough, bad guys are escaping Hell and attacking Earth!
-Wrath of the Dragon: An ancient warrior is freed from a mysterious music box, and warns of an impending threat. Soon enough, the Z-Fighters find themselves in battle against a deadly, giant monster.
-The Path To Power: A retelling of how Goku first met his friends, but with the Red Ribbon Army as the villains.
-A Hero's Legacy: Set 100 years after GT, this one tells the story of Goku's young ancestor and his own personal journey.
-Yo! Goku and his Friends Return!: Set 2 years after Buu's defeat, two tough soldiers from Frieza's old army come to Earth in pursuit of a young Saiyan - one that has ties to Vegeta.
-Plan to Eradicate the Super Saiyans: An HD remake of the Plan to Eradicate the Saiyans "lost movie." However, it isn't just a remake, it adds in extra scenes and takes several out from the original as well.
-Episode of Bardock: A sequel to the Bardock: The Father of Goku movie, regarding Bardock being sent back in time by the attack that was supposed to kill him, and facing Frieza's ancestor in battle. Edit
1) Saban/Ocean Group dub. Recently released under the Rock The Dragon set.
2) FUNimation dub stand-alone DVDs. These feature both dub and sub versions of the show and are uncut as far as footage goes, however they lack the eyecatch sequences and "next episode" previews. These discs only cover from about halfway through the Frieza Saga to the end of the Z series (basically where the "edited" DVDs listed above left off.)
3) Ultimate Uncut Edition. Uncut sub and dub DVDs starting at the beginning of the Z series, this was FUNimation's attempt to "bridge" the series by making uncut DVDs of episodes that had only previously been released edited (see section 1.) However, FUNimation aborted this line in favor of doing "season sets" and stopped in the Saiyan/Vegeta Saga, before it reached the end.
4) "Orange Brick" Season Sets. This marked the first time FUNimation released Dragon Ball Z on home video in its entirety. These feature 3 audio tracks - Dub with the Japanese music, Dub with FUNimation music, and the original Japanese version. However they quickly came under controversy for using heavy digital noise reduction and cropping the picture, so as to format the picture for widescreen televisions.
5) Dragon Box sets. These sets rectify the problems of the Orange Brick Season Sets - featuring a frame-by-frame remastered version of the show and no cropping. However, much to the chagrin of some fans, they do not include the FUNimation version music track. They still feature uncut dub and sub versions, however.
6) Blu-Ray release. These started coming out in November of 2011, and the first two sets featured the best picture quality ever seen on a Dragon Ball home video release, featuring a clean presentation true to the source material. Unfortunately, FUNimation cancelled this line due to the costly nature of the restoration.
7) New Blu-ray season set release. Will be released starting at the end of 2013. Unfortunately, FUNimation is cropping the picture again to make the set fit widescreen televisions.
We encourage you to look for your USA/English versions of Dragon Ball Z in it's own IMDb English title page Dragon Ball Z (1996). You can ask any question related to the English versions in the boards.
If you have any question regarding the Japanese releases, please feel free to post in this title page board. Edit
This question is asked heavily on the message boards, even though it is explained in the series - no one can be wished back to life with the Dragon Balls who has been dead for over a year.
Additionally, no one can be wished back to life (regardless of how long they have been dead) who has died of natural causes. Edit
Three sets of Dragon Balls exist, that we see in the series. Each consists of seven balls, and can grant a wish (or wishes) when brought together.
-The Earth Dragon Balls. The best-known set, which are the ones regularly hunted down and collected by our heroes. They were created by Kami, after he expelled the evil from his body that took the form of King Piccolo. They grant a single wish. These balls are about baseball-sized, and they are capable of bringing back any number of deceased people back to life with a single wish (provided they are able to be wished back, some restrictions apply.) Shenron (the Eternal Dragon summoned by the balls) These Dragon Balls can not wish someone back to life more than once, as Shenron will not grant the same wish more than once. They become inert for a year after being used. Later, when Dende becomes guardian of the planet, he upgrades the balls so that they can grant two wishes, however they still can not bring people back to life more than once.
-The Namekian Dragon Balls. These are introduced during our heroes journey to the planet Namek. They are much larger than the Earth Dragon Balls, roughly basketball size. They were created by the Grand Elder of the Planet Namek. These balls have some tremendous advantages over their Earth counterparts - they grant THREE wishes instead of just one, and can bring someone back to life an infinite number of times, provided the person did not die of natural causes. Furthermore, they are only inert for 1/3 as long as the Earth's Dragon Balls. However, they do feature the disadvantage of only being able to revive a single dead person with a single wish - this was eventually changed following the founding of the planet New Namek, when Moori became the new Grand Elder.
Black Star Dragon Balls - These only appear in the anime-only series, Dragon Ball GT. They are hidden in Kami's lookout, and were created by Kami before he separated the evil King Piccolo side from within, meaning they are far more powerful than any other Dragon Balls. They are so powerful that they can grant virtually any wish, including some even the original Dragon Balls would not be capable of (though exactly what all they are capable of is never truly and fully explored.) The strength of these Dragon Balls comes with a huge drawback - after being used, the balls scatter across the entire universe - and if they are not gathered back together on the planet where the wish was made, the planet is destroyed a year later. Edit
This is easier to answer in the manga version of the show, as it lacks all the movies/filler/GT series/etc.
In the original manga version of the series, the most powerful character is Super Saiya-jin Vegito.
In the anime, the answer is still unknow, due to the current airing in Japan of Dragon Ball Super. Edit
Hirotaku Suzuoki passed away in 2006 following a battle with lung cancer. He was best known for voicing Tien, but also voiced the World Martial Arts Tournament Announcer, the Otherworld Tournament announcer, and some GT characters as well.
Kohei Miyauchi passed away in 1995 from abdominal varices. He was well known in the franchise as the voice of Master Roshi, voicing the character from the beginning of Dragon Ball, up until the Buu Saga. Interestingly, his final scene voicing Roshi is where he was killed by Buu, turned into chocolate and eaten. This scene was recorded less than 3 months before Miyauchi's death.
Daisuke Gori committed suicide in early 2010 after being diagnosed with an illness that was taking away his eyesight. Of all of the Japanese voice actors, Gori had what was arguably the most impressive roster of voice acting for characters on the show, largely due to his deep, distinctive voice. Gori voiced Hercule Satan, Master Roshi's Turtle, King Cold, Ox King, King Yamma, Captain Yellow, Porunga, and countless others.
Takeshi Aono died in 2012, following ongoing complications from a stroke he had in 2010. He voiced King Piccolo, Kami, and Ninja Murasaki.
Isamu Tanonaka passed away in 2010, as a result of myocardial infarction. Tanonaka was better known for voice acting in other animes, but in the Dragon Ball franchise he voiced several brief but memorable characters, including Raiti (one of a pair of aliens masquerading as a Namekian), and Bibidi (the father of Babidi that only appears in a flashback in the anime.)
Kenji Utsumi, known to Dragon Ball fans as the voice of Shenlong, passed away in 2013 from cancerous peritonitis at the age of 75. He was the voice of Shenron (on most occasions), Commander Red, Mutaito, and Recoome (the latter character being recast in more recent Japanese versions of the show, though.) Edit
FUNimation's dub version is infamous for making some major blunders with series information. These are a few such errors:
-Raditz says Planet Vegeta was destroyed 3 years ago when he arrived on Earth, when it was actually closer to 20 years. This is a major plot hole for the dubbed version. For that to be true, Goku arriving on Earth and the entire first Dragon Ball series, and the years between Dragon Ball and Z would have to be crammed into a 3-year period, which is simply not true.
-An ogre tells Goku Snake Way is 10,000 miles long, when it is actually closer to 1,000,000 kilometers. Goku once ran/swam 10,000 miles or so as a child in one day to get to the Tenkaichi Budokai, so if it were "only" 10,000, Goku would have gotten to Kaiô in no time flat.
-Vegeta tells Goku that Goku's father Bardock invented the Saiyan "Power Ball" technique to create artificial moonlight (this is addressed above.) However this is one of the few self-made plot holes FUNimation actually corrected in their initial re-dubbed version. Edit
NOTE: This is a question that confuses viewers of the English version.
To avoid confussion between viewers of the Japanese original/dubs that kept the original japanese names, it is important to notice that:
- The Spirit Bomb is the English name for the Genki Dama technique.
- The Spirit Ball is the English name for Yamcha's Sôkidan technique.
- Wolf Fang Fist is the English name for Yamcha's classic attack, Rôgafûfûken.
Now, to answer the question:
This is another common thing that confuses viewers of the English dubbed version of the show. Yamcha DOES NOT know the Spirit Bomb, and never learns or uses it.
When Goku trains with King Kai (North Kaiô), he learns a technique called the Spirit Bomb (Genki Dama), which entails gathering energy from all living things and life energy on a planet, and harnessing it into a powerful sphere of energy.
In an earlier episode, where Yamcha and other Z-Fighters go back in time to fight Saiyans of the past, he uses a technique where he charges up energy into a ball and heaves it at his enemies, being able to control it with his hand and finger motions. It sounds like he says "Spirit Bomb" before he throws it.
If one listens closely, he is actually saying "Spirit BALL." Though they are similar looking attacks, the two are actually very different. Goku's technique cannot be guided or controlled, and while Yamcha's move can be controlled, it is nowhere near as powerful as Goku's move.
Goku's Spirit Bomb technique is called "Genki Dama" in Japanese, which roughly translates as "Energy Ball."
Yamcha's Spirit Ball is called the "Sôkidan" in Japanese, which roughly translates as something like "Spinning Ki Turn." The move was intended as a replacement for Yamcha's old signature attack, the Rôgafûfûken/Wolf Fang Fist (which he never uses after Dragon Ball ends), though it was never heavily used, as Yamcha was gradually relegated to a background character over the course of the Z series.
Long story short, Yamcha DOES NOT know the Spirit Bomb. His Spirit BALL technique is an entirely different move. Edit
There are a few points to cover here.
First and foremost, Dragon Ball GT is an ANIME ONLY series, and is not canon to Akira Toriyama's original manga. When there are anime-only pieces of content, factors like this are often not taken into consideration and some plot holes are created. This was most likely the case here.
As far as an actual "in series" explanation goes, it could be argued that Pilaf, despite his malicious intent and unkind ways, is more of a "comic relief", less serious villain than many others, and is not considered to be truly evil.
One other possible explanation is that he and his henchman fled the earth during the Majin Buu crisis and were never killed at all. Given that Pilaf has tons of technology at his disposal this is a strong possibility. Edit
You've got good reason to be confused, but the answer to these question is quite simple:
These are anime-only filler scenes not found in the original manga.
The anime focuses heavily on a lot of scenes set in Hell, often for the purpose of creating further filler scenes and story arcs. While Akira Toriyama did give Toei Animation permission to create filler scenes to "pad out" the anime so it would not run ahead of the still-in-production manga at the time, they clearly did not take a number of factors into consideration, which result in many plot holes here and there. This is just one of many examples. Edit
Because they aren't on Planet Vegeta.
Nowhere in the original Japanese version of the show does it state that the world they meet these past Saiyajin on and do battle with is Planet Vegeta. There is one mention of the planet's name in the English dub, but this is one of many dubbing mistakes. This is most likely another planet altogether where the Saiyajin did battle, likely trying to conquer it for the World Trade Organization that Freeza rules over.
This is one of many anime-only filler episodes, but unlike a lot of the filler, this one is easily explainable and fits into the story fine, free of plot holes, as the only real error stems from a dubbing mistake.
It is also possible there is more than one planet called Vegeta, seeing as how someone like Freeza rules over no less than 79 worlds. Edit
This is another "anime-only filler strikes again" moment. But if one looks closely, it is something that can be explained.
In the time period Goku travels back to, Mutaito is clearly in the prime of his life, and his martial arts school is at the peak of its popularity. When Piccolo Daimao attacked the world much later on, it is likely Mutaito was at an older age and nowhere near as strong as he was when his martial arts school was going strong. In an older, weakened state, he likely had no chance defeating Piccolo, and was forced to use the Mafûba instead, costing him his life. As this is anime-only filler, with Goku going back in time, this explanation is strictly theory and not explicitly stated by the creators of the manga/anime. However it does provide a possible explanation. Edit
Following the defeat of Evil Kid Buu, ten years pass. The Z-Fighters head to the World Martial Arts Tournament. By this time, Gohan and Videl have gotten married, and now have a daughter named Pan. Pan does very well in the fights, despite only being a few years old. Goku also reveals that he made a wish to the Shenlong to reincarnate Kid Buu as a human being. The human being is an Indian boy from a poor village named Uub (Buu spelled backwards, appropriately enough.) Uub is set to fight Goku in the tournament, but lacks any real will to fight. Goku insults him and his family in an effort to get him to power up, which works. He begins exhibit power on-par with the Z-Fighters once powered up. The end of the series is Goku and Uub flying away to Kami's Lookout, where Goku promises to train the boy.
Dragon Ball Z was followed up by another anime series called Dragon Ball GT, which continues the story line. However it was not based on a manga by Akira Toriyama, and is generally not considered canon. Toriyama had only minor involvement in GT (much like the theatrical movies.)
Currently, Dragon Ball Cho: Dragon Ball Super, is taking the story right after the defeat of Evil Kid Buu, and author Akira Toriyama has major involvement in the storyline and new characters. Edit
Goku: Lost his sanity when Freeza killed his best friend Krillin.
Mirai Trunks: Went into a fit of anger when he found the dead body of Mirai Gohan, who has been killed by the Androids (this contradicts the manga, which showed in a special chapter that Mirai Trunks could become a Super Saiya-jin before Gohan's death.
Vegeta: After rigorous training in space, Vegeta grew frustrated that his training was getting him nowhere. He lost his patience and went into a fit of rage at his being unable to reach the level of Super Saiya-jin, which ironically caused his first transformation. Not showed in the anime.
Gohan: While training in the Time Chamber, Gohan keeps trying to reach this level of power, but never quite manages to get it down. Eventually, he thinks of all the villains who have terrorized the Earth and how he was unable to provide the level of help he should have. It is this guilt trip that causes his first true transformation.
Goten: Casually transforms during a sparring session with Chichi (it's possible he achieved the form with relative ease since he was conceived after Goku had already become a Super Saiya-jin). (
Trunks: Never revealed. Though given that he trained with his father Vegeta his whole life, his transforming was more-or-less inevitable.
All other characters who became Super Saiya-jins were either non-canon characters (either from GT, filler scenes or movies) or fusions of characters who already knew how to become Super Saiya-jins. Edit
Son Gokû wasn't a merciless killer. He hit his head being a young baby, when Grandpa Son Gohan found him, and he forgot everything about being a Saiya-jin and his mission. The first time he ever killed someone was under Ôzaru form, without any awareness of what he was doing, when he accidentally killed Grandpa Son Gohan. He never knew the truth until years after.
He never willingly killed any of the Red Ribbon Army members neither.
He killed Piccolo Daimao probably because he was the one who killed his best friend Krillin, and lead his Master, Kame Sen'nin, to a fatal end . After he became a father himself, and an adult, he became aware of his strength and start showing his characteristic merciful side, by not killing his enemies (unless there is absolutely no other choice). Edit
There are several, including a number of non-canon ones from movies/filler/GT/etc.
Ôzaru: Any Saiya-jin with a tail who sees moonlight or the light from a Power Ball is capable of this. Examples we see in the series and movies include Goku, Gohan, Vegeta, and Bardock and his team. Numerous other Ôzaru (Great Apes) are shown in anime-only flashbacks. Raditz and Nappa do not use the transformation in the anime or manga, but can do it in the videogame Budokai Tenkaichi 3 where a moon is available.
Super Saiya-jin: The form that Z really heavily popularized. It takes a pure heart, a high enough power level, and often some sort of traumatic event or distress to be pushed to reach this form. And at least being half Saiya-jin. Goku, Trunks (both future and preset), Vegeta, Gohan, and Goten all achieve this form, as do their respective fused forms (Gotenks, Gogeta, Vegito.) There are several variations on the "first" Super Saiya-jin form, including the "second grade" form with slightly bulked up muscles (Vegeta calls himself "Super Vegeta" in this form), and the "third grade" form (often dubbed things like "Ascended Saiyan, Ultimate Super Saiyan, or Ultra Super Saiyan), which further bulks the character up to higher levels of attack and defense, but at the expense of speed as well as rapid power drainage, making it an impractical form to use in battle. Goku, Vegeta, and Future Trunks were all capable of the "third grade" form, but only Trunks used it, Vegeta and Goku knowing about its limitations.
Super Saiya-jin 2: The next main Super Saiya-jin form. This is similar to the "ascended" versions of Super Saiya-jin, but with all abilities balanced and no negative limitations. Gohan was first to achieve this form, but Goku and Vegeta later did as well, presumably in the 7 years between the Cell and Buu Sagas. It is implied that their fusions would be capable of this form as well, as Gotenks can apparently be Super Saiya-jin and Super Saiya-jin 3 and "skip over" the form.
Super Saiya-jin 3: The only non-fused character capable of this transformation is Goku. It is far more powerful than the previous states, but rapidly drains the user's energy. Gotenks can achieve the form as well. Several "what if" scenarios occur in video games, showing Vegeta, Future Trunks, and Broly in this form.
Super Saiya-jin God: A new form introduced in the Battle of Gods movie, which only Goku reaches. Made canon in Dragon Ball Super.
Controlled Super Saiyan/Legendary Super Saiya-jin: The forms used by Broly, the Legendary Super Saiyan. No other character is shown using them.
Golden Great Ape: A transformed, golden "Super Saiyan" form of Great Ape. Achieving this form is necessary to reach Super Saiyan 4. In old Saiyan legends Vegeta talks about, he mentioned how the last Super Saiyan could only be one in the transformed state, meaning he is likely talking about Golden Great Ape. Goku and Vegeta are shown in this form.
Super Saiya-jin 4: A new form of Super Saiya-jin seen only in Dragon Ball GT. Appearance is radically different from previous forms of Super Saiya-jin, and the user must first achieve the Golden Great Ape form. This form, apparently, takes the user to their body's "prime", meaning even Goku turned into a child achieves an "adult" form. Only Goku and Vegeta are seen in this form, as is their fusion, Gogeta.
Super Saiya-jin God Super Saiya-jin: Shown in the movie "Resurrection 'F' " both Goku and Vegeta can achieve it . Probably will become canon in Dragon Ball Super. Edit