This state can be achieved by harnessing absorbing an extreme amount of extra Saiya Power. It possesses much greater power than the ordinary Super Saiyan 4 form. It likewise equally enhances his senses, letting him react to practically any threat. He is also shown able to absorb enemy energy attacks, nullifying their damage. This state is symbolized by a radiating red glow from his entire body.
Usage and power
Goku first used this form in battle against Baby. With the mutant Tuffle having combined his power with that of Vegeta's in the Golden Great Ape and Goku too exhausted from the prolonged battle, Goku called on the aid of Gohan, Goten, Trunks, and Pan. Their combined donation not only restored his full capacities, but continued on into an even more power state that pushed his body well-past his normal limits. With the power of this state, Goku quickly overwhelmed Baby Vegeta, able to even catch and absorb his Revenge Death Ball before finally defeating him.
Goku goes on to use this form in battle against Syn Shenron, taking energy from the Super Saiyans Gohan, Goten, and Trunks to restore his full power, but then continues to take in even more power from them to push his body past his limit - at the risk of it killing him. With the power of this form he is able to overwhelm Syn Shenron, the latter being no match for him in power. However, he in turn is overwhelmed by Omega Shenron, and though his Dragon Hammer is able to obliterate Omega Shenron, the dragon manages to regenerate.
Video Game Appearances
Though it does not appear in Xenoverse 2 this powered up state is possibly referenced by Super Saiyan 4 Goku's Super Soul, Full-Powered Super Saiyan 4! which largely boosts normal attack power when the user is revived.