While the characters of Isaac Yankem, DDS and the fake Diesel were not direct steps in Kanes evolutionary process, theres no doubt that they played an indirect role in the journey to the Big Red Monster. Without the failure of Glenn Jacobs prior characterizations, fans would never come to know Kane. Glenn Jacobs spent a number of years under contract to the World Wrestling Federation prior to his debut as the Undertakers evil brother. While the fake Diesel and Isaac Yankem gimmicks have ultimately been recorded in the history books as utter failures, they did have a small smattering of shining moments. As Yankem, Jacobs was inserted into a top-tier feud with the Federations most established star of the New Generation era, Bret The Hitman Hart. While the character had a relatively short run and was ultimately deemed a flop, Isaac Yankem did make a decent impact within the Federation. However, Glenn Jacobs would return to the WWF just two years later as a completely new and more impactful superstar.