Super Full Power Saiyan 4

Super Full Power Saiyan 4 emerged during the climactic final battle of Dragon Ball GT, when standard Super Saiyan 4 Goku found himself unable to match Omega Shenron's overwhelming power. Omega Shenron, having absorbed all seven cracked Dragon Balls and their corresponding Shadow Dragon abilities, was simply too strong for any individual fighter to handle alone.

The solution came through the collective power of Goku's family and allies. Pan, Gohan, Goten, and Trunks channeled their Saiyan energy into Goku, providing a massive external power boost that elevated his Super Saiyan 4 form beyond its normal limits. The infusion of additional Saiyan ki pushed the transformation to a level commonly referred to as its "ultra full power" state, granting Goku the strength needed to finally overpower Omega Shenron.

This moment served as Dragon Ball GT's thematic capstone, emphasizing the importance of bonds between fighters over individual power. Goku, throughout his entire journey from child to adult to legendary warrior, had always been strongest when supported by the people he cared about. Super Full Power Saiyan 4 literalized that theme, turning the love and strength of his family into a tangible combat advantage. The Universal Spirit Bomb that followed used this principle on an even grander scale, gathering energy from the entire universe to deliver the final blow against the Shadow Dragons.