Koola
    Koola is even more powerful than Frieza, his brother.  Koola is also the son of King Cold.  Koola, like Frieza has a tail that bears a strong resemblence to a lizard's tail.  Koola also had the ability to transform.  He could make himself much more powerful by transforming.  Once Goku went Super Saiyan though, he (Koola) was basically out of the fight.  The huge energy ball he threw at Goku was repelled and shot back to him.  He then rode his energy ball (against his will) into the sun.  But Big Gheti Star (a microchip which had grown into a large ship) salvaged him and made him the brain of the ship.  After Big Gheti Star had all his DNA, it could make duplicates of him made entirely out of metal.  These "Metal Koolas" can reproduce any broken part almost instantly.  This caused a huge problem for Goku and Vegeta.  Eventually, the metal Koolas rounded up Goku and Vegeta and Big Gheti Star was absorbing their Super Saiyan energy so it could make millions of metal Super Saiyans.  Goku and Vegeta had too much energy though, and Big Gheti Star/Koola absorbed too much energy and blew up.  It was then gone for good.
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