The Kyurangers answer a distress call from Lucky’s home system in episode 36 of Uchu Sentai Kyuranger, The Legend Sleeping on Lucky’s Home-World.
The Kyurangers are headed toward Don Armage’s base when they catch a rescue signal. It comes from Planet Ruth, a star in Lucky’s own Leo Minor system. Lucky heads toward Planet Ruth, and the Leo Minor System’s Karo known as Wunjet is there attacking everyone. There are friends here that Lucky made as a child, as well as a mechanized life form named Caesar, and an old man who raised them as if he were a grandparent. The Kyurangers put up a fight, but Wunjet kidnaps Caesar. Lucky goes to save Caesar from Wunjet. Meanwhile, Hammy and the others listen to the grandpa talk about Lucky from his time on Planet Ruth.