Mirror spaceship

The Mirror spaceship (謎の宇宙船, Nazo no uchuusen; lit. "mystery ship") is a spaceship that first appeared in a filler episode of Dragon Ball Z, "Journey to Namek".

Story
When Gohan, Krillin, Alexis, Carlos, Rad and Bulma set out on the journey to Namek, they are attacked and captured in an invisible spaceship. They find out that the only passengers of the spaceship are children led by a boy named Zeshin. Their planet was attacked by a squad of Frieza's army, which was led by Cui. The fact that the ship was made of mirrors (and thus invisible) was the only reason why they managed to escape from Frieza's blockade during his attack on the planet. The mirror spaceship has landed on Earth under Alexis' idea.

Video game appearances
The Mirror spaceship appears in Dragon Ball Z II: Gekishin Freeza. The player can get secret information here.