Other source:
Everyone that has been killed by Frieza and his henchmen on Namek are resurrected, but so far, Guru isn't back yet and it looks like Goku has been beaten by Frieza's attack. To avenge his father, Gohan returns to the battle to make sure the cold tyrant blows up with the planet, but is no match for Frieza. Before Frieza lands the killing blow, however, Guru returns to life, and Goku reappears, and orders Gohan to leave Namek.
