Tenchi Muyo! Ryo-Ohki S01E06 - We Need Tenchi!

The girls head for Kagato's ship to avenge Tenchi. Meanwhile, on Earth, Sasami senses Tenchi is in trouble and summons Tsunami, her own Juraian battleship, to save him from near-death. Mihoshi accidentally releases a 20,000-year-old scientific genius, Washu, from Kagato's imprisonment, who turns out to be Ryoko's true creator, and Tenchi returns to face Kagato in a battle to the death.