Combined attacks by 17 and Frieza destroy Jirens barrier and following Goku and Frieza teaming up to take Jiren out of the ring, Android 17 becomes the only contestant remaining, winning the tournament and wishing for all the universes erased during the tournament to be restored.
Why did Android 17 win the tournament?
When asked what his wish would be, he wished to bring back all of the eliminated universes instead of his cruise around the world with his family. Good thing he did this too, as the Grand Priest revealed that the Zenos had believed that the winner would be of pure heart and would revive the fallen universes.
How did Android 17 survive the tournament?
As 17 taunts Cell to come back out, Cell begins to emerge from the ground behind him. Android 17 is ultimately killed when Semi-Perfect Cell self-destructs on King Kais planet. 17s life is restored after the Z Fighters use the Dragon Balls to revive those who died as a result of Cells campaign.
Who did Android 17 beat in the tournament of power?
Goku and Frieza sacrificing themselves at the very end to take out Jiren allowed 17 to be crowned the winner. 17 didnt beat Jiren by his own devices, but he did manage to hang on for more than 30 episodes of non-stop fighting.
How did 17 self destruct?
The fighter is powerful enough to not need a bomb for such an act; Android 17 just needed his energy to self destruct. In order to blow himself up, Android 17 raised his power to such an extreme level that he exploded. The fighter used his self-sacrifice to divert an attack which Jiren sent at Goku and Vegeta.