A line of mobile suits produced by Zeon toward the end of the the One Year War. The Gelgoog outclassed most mobile suits of the time, and some of its later variations, produced in extremely small numbers shortly before Zeon's defeat at A Baoa Qu, were even stronger (variants such as the Gelgoog Jaeger, High Mobility Type, Marine, etc.).
Some argue that if the Gelgoog had been produced earlier in the conflict, Zeon would have been victorious, however the Gelgoog was simply too little, too late.
Both Johnny Ridden and Char Aznable piloted variations of the Gelgoog at the end of the One Year War.