The most exciting aspect of Dragon Ball apart from its fights is perhaps the characters' awesome transformations. Fans have witnessed heroes and villains alike go through multiple transformations throughout the franchise. The moment a character transforms, especially for the first time, is always thrilling for fans to see. No one in the entire franchise has more transformations than Goku.
These transformations usually happen within the context of huge battles or emotional moments that bring fans to the edges of their seats. Goku's Super Saiyan transformations are so iconic that even people who don't watch Dragon Ball are aware of what Super Saiyan is. There are numerous episodes in which Goku goes Super Saiyan in epic ways but the following are arguably the most memorable.
Goku Transforms Into a Super Saiyan for the First Time
Goku transformed into a Super Saiyan for the first time in Dragon Ball Z Season 3 Episode 21 (Episode 95 overall) "Transformed at Last." It happened while Goku was in a fit of rage after watching Frieza kill Krillin, his best friend since childhood. To say this episode left fans stunned would be an understatement. Super Saiyan seemed like a mere myth up until the moment Goku transformed. There had been quite a bit of foreshadowing leading up to the scene that would change the series forever. This included the fact that rumors of the powerful form were the main reason Frieza destroyed Planet Vegeta. Fans had no idea at the time that this was just their first taste of many more Super Saiyan transformations to follow. This moment will forever be one of the most iconic in the franchise.
Goku Meets Future Trunks
This moment which happened during DBZ Season 4 Episode 15 (Episode 122 overall) "Mystery Revealed" isn't memorable because it was during an important battle or an emotional sequence. It was satisfying for fans because it was only the second time Goku transformed into a Super Saiyan on-screen, and the first time he did it casually. Goku had just returned to Earth and reunited with Gohan and his friends shortly before the awesome moment, after being absent for several episodes. Everyone's awed reactions to his transformation made the moment all the more epic.
Goku wasn't the only reason this moment is a favorite. Trunks, who was a complete mystery at the time, also transformed. It was the first time two Super Saiyans shared the screen together and it was electrifying for fans to watch. As if that wasn't exciting enough, the two engaged in a quick display of skill and strength as they clashed for a brief but enthralling moment. Viewers got their first glimpse at how incredible a fight between two Super Saiyans could be.
Goku Goes Super Saiyan 2 to Fight Vegeta
This happened in DBZ Season 8 Episode 10 (Episode 229 overall) "Vegeta's Pride" and wasn't the first time viewers saw a character transform into Super Saiyan 2. Nonetheless, it was the first time Goku and Vegeta were shown using the form. That alone made this a noteworthy moment. However, what truly makes it unforgettable is the fact that it came when Goku and Vegeta were finally about to engage in their rematch. This rematch had been teased and built up for years, mostly through Vegeta's constant need to reach or surpass Goku's level.
Fans remember this fight as one of the best in the entire series. It should be noted that this wasn't the first time Goku went Super Saiyan 2, it was simply the first time viewers saw him do it. He actually learned the transformation off-screen and just never needed to use it until this fight. Another interesting thing about this form is that it was the first and last time Goku wasn't the one to reveal a new Super Saiyan transformation. Fans were already fully familiar with the form, having first seen Gohan use it when he fought Cell.
Goku Shows Majin Buu Super Saiyan 3
Goku showed off his Super Saiyan 3 transformation for the first time in DBZ Season 8 Episode 26 (Episode 245 overall) "Super Saiyan 3?!" When he first displayed this form on-screen, both viewers and the characters who witnessed it were equally shocked. It was the most unique Super Saiyan form yet as Goku's hair grew in length past his waist and he lost his eyebrows. In the scene, Goku demonstrated his different Super Saiyan forms to keep Majin Buu distracted so Trunks could get the Dragon Radar. The transformation was so powerful and intense that it literally shook the entire Earth. Majin Buu was in complete awe and Babidi who wasn't interested in what Goku had to show was suddenly fearful. It's easily one of the most stunning and memorable moments in the Babidi Saga.
Goku Turns Into a Super Saiyan God
The Super Saiyan God transformation debuted in the anime in Dragon Ball Super Episode 9 "Sorry for the Wait, Beerus Sama. The Super Saiyan God Is Finally Born!" The episode was a part of the episodic adaptation of the movie Dragon Ball Z: Battle of Gods. In other words, the transformation was initially revealed in the movie. Goku learned about this form from Shenron and then used it in order to keep Beerus from destroying the planet. Most (if not all) fans probably thought they'd seen the last of new Super Saiyan transformations with Super Saiyan 3 and then came this one. It was a pleasant surprise of epic proportions. What makes this form visually unique is that Goku's hair is red and his aura looks like literal fire. Goku and Beerus put their God-level strengths on display as they fought each other in an incredible battle.
Goku Surpasses Super Saiyan God
This form was revealed in Dragon Ball Super Episode 24 "Clash! Frieza vs. Son Goku! This is the Result of My Training!" Like Super Saiyan God, this form was initially revealed in a movie, Dragon Ball Z: Resurrection F, but was later adapted into episodes. Goku was reunited with his long-time enemy Frieza due to the latter seeking revenge. Despite Frieza saying he wanted revenge, the two were more like friendly rivals than enemies at this point. Nonetheless, they both pointed out that they were hiding their true strength from each other, and this led to Goku revealing Super Saiyan God Super Saiyan or simply Super Saiyan Blue.
The existence of a level beyond the form that literally has 'god' in its name had fans fascinated. Viewers were enthralled by the moment especially since Goku was about to use this form against Frieza. The two have an interesting history and Frieza is a beloved character despite being one of the franchise's most notorious villains. Super Saiyan Blue is essentially the Super Saiyan form of Super Saiyan God. Goku's hair and aura are, of course, blue in this form. It is currently the strongest Super Saiyan form (Ultra Instinct not being a Saiyan form) to date.