Throughout the entirety of the Dragon Ball series, there has been one attack used by Goku that stands above all others as the ultimate finisher, and Dragon Ball GT gave it a cosmic upgrade.
Before Goku became a Super Saiyan to stop the seemingly unbeatable villain, Frieza, there was another last-ditch technique he planned to use against the intergalactic dictator to take him out as quickly as possible: the Spirit Bomb. The Spirit Bomb is a technique that pulls energy from every living thing on any given planet, and concentrates that energy into a nearly unstoppable ball of unparalleled power. When Goku first fought Frieza, he created a Spirit Bomb and threw it at the villain. While Frieza was able to dodge it, he was nearly consumed by its power, and he made it clear that he might not have survived if the Spirit Bomb did hit him–and Buu is proof of that. At the end of Dragon Ball Z, Goku created a Spirit Bomb from the energy of everyone on Earth and New Namek to kill Majin Buu, which not only redeemed the attack after it failed against Frieza, but also cemented it as DBZ’s ultimate finisher move.
Dragon Ball GT Made Goku’s Spirit Bomb Even More Powerful
In Dragon Ball GT episode 63 (written by Atsushi Maekawa, directed by Osamu Kasai, produced by Toei Animation), Goku is believed to be dead after suffering a catastrophic blow delivered by Omega Shenron. Omega Shenron is a Shadow Dragon who absorbed the power of every Dragon Ball, making him the living embodiment of the collective evil manifested throughout the course of the whole series. Essentially, Omega Shenron is Dragon Ball’s ultimate villain, and his power level proves it. Not even Super Saiyan 4 Goku and Super Saiyan 4 Vegeta fighting side-by-side could defeat this monster. In fact, Goku used up so much of his energy trying, that he reverted to his original form right in the middle of the fight. It was at this moment that Omega Shenron seemingly killed Goku, with Vegeta not too far behind him. However, from the bottom of a crater created by Omega Shenron, where it was believed Goku was reduced to a lifeless corpse, Goku was creating an attack that put the original Spirit Bomb to shame: the Super Ultra Spirit Bomb.
Goku’s first Spirit Bomb against Frieza pulled energy from Planet Namek while his second Spirit Bomb against Kid Buu pulled from both Planet Earth and New Namek. The Super Ultra Spirit Bomb he used against Omega Shenron, however, was pulled from planets across the entire universe. What makes this attack more awesome than the obvious–that being the literal cosmic upgrade given to the Spirit Bomb–is that Dragon Ball GT was setting this move up from the start. GT showed the Z-Fighters going to far-off worlds in search of the Black Star Dragon Balls at the beginning of the series, all the while making allies along the way. So, when Goku needed their energy to make the Super Ultra Spirit Bomb, those Goku helped earlier in the anime gave their power up freely to help Goku in return.
The Super Ultra Spirit Bomb is the perfect finisher move for the series, as it not only upgrades the previously established power of the Spirit Bomb, but it also ties a perfect bow around the entire series by tying it back to the start of GT. Dragon Ball GT gave Goku’s ultimate finisher a cosmic upgrade, and arguably the coolest part of that upgrade is the proof of Goku’s heroic impact across the universe.