#4 Chris Jericho
Back in 2001, Chris Jericho was two years into his WWE career. He was a major player in The Invasion angle, taking the side of the WWE. Around this time, tensions started to rise between Y2J and The Rock. At No Mercy that year, the pair faced each other for the WCW Championship, with Jericho coming out on top.
The day after this, however, the pair came together to form a tag team, quickly defeating The Dudley Boyz to win the Tag Team Championship. This made Jericho a double champion, a reign that lasted a little over two weeks.
The duo lost the titles to the team of Test and Booker T, which reignited the rivalry between The Rock and Jericho. This was marked by Jericho brutally attacking his former tag team partner with a steel chair after their loss, turning heel in the process.
Not long after this, Jericho again became a double champion, beating The Rock to retain the World Championship, and Stone Cold Steve Austin for the WWE Championship. This meant that Jericho was the first-ever Undisputed Champion and the fourth Grand Slam in WWE.