Son Goku Is the Strongest After All!! Majin Buu Is Annihilated
With the full energy of humanity gathered, Goku hurls the massive ultimate attack directly at Majin Buu. Yet even facing such overwhelming power, the monster continues to resist, turning the final moment into a grueling test of endurance. As Goku's strength falters under the strain, a crucial, last-second intervention breaks the deadlock and decides the fate of the universe.
Aired 14/06/2015EP 59 - Son Goku Is the Strongest After All!! Majin Buu Is Annihilated
Dragon Ball Z Kai: The Final Chapters
Since Cell's defeat Gohan has grown up and go to the university then she meets Videl which who has some adventures, then both and his new brother Goten are training for the new tournament, in which Goku came back from the dead for one day. In half of the tournament a misterious persons advice the group about the resurrection of the dangerous Majin Boo, but all plans fails and every one try new ways to stop The dangerous Majin Boo who gets stronger each time. Goku and his friends make everything for stopping them through fights.
(Source: Anime News Network, edited)
Note: Remastered version of the Majin Boo arc that adheres more to the manga's story.