Found You, Gohan! Harsh Training in the Kaioushin Realm!
While Majin Buu continues his uninhibited destruction across the Earth, Gohan remains in the Sacred World of the Kais, focusing all his energy on mastering the massive Z-Sword. As the young Saiyan slowly gets a handle on the blade's incredible weight, his training takes an unexpected turn that completely alters the Supreme Kai's strategy.
Aired 16/11/2014EP 32 - Found You, Gohan! Harsh Training in the Kaioushin Realm!
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.