Gogeta is neither Goku or Vegeta, but the instrument of Janemba's defeat. That's a famous quote from Gogeta. Gogeta is the fusion result of Vegeta and Goku when the fusion dance is performed. The first time theses 2 attempted this fusion they turned out as Gogeta, but he was really fat and his only attack was farting on people. The second attempt proved a success, and they got it right and made a super powerful fighter. Gogeta fought vs Janemba in the DBZ movie 12, but he also fought the Evil Shenlongs in DBGT. He is very strong, in my opinion stronger than Vegetto, but the problem is he only lasts 30 minutes; until he get's seperated again into Goku and Vegeta. He is also a SSJ4 fusion when Vegeta and Goku fuse in SSJ4 form. I think he is one of the best fusions.