#2 Shawn Michaels and Bret Hart's rivalry had a huge impact on WWE
Bret Hart and Shawn Michaels were two of the most popular Superstars in WWE during the 1990s. Naturaly, the duo engaged in a war on and off-screen. They had numerous battles throughout the decade, and their feud regularly offered dynamic programming.
Out of their numerous bouts, two of them undeniably stand above the rest. The first was the main event of WrestleMania XII, in which HBK defeated Bret Hart to capture his first WWF Championship.
The second was the infamous Montreal Screwjob, which took place at Survivor Series in 1997 in Hart's home country, Canada. Hart, who was about to go to WCW, did not want to drop the championship to Michaels because of their numerous personal issues. For example, Michaels publicly accused Hart of having an affair with Sunny.
So Vince McMahon legitimately stole the championship from Hart in one of the most infamous and controversial moments in pro wrestling history.
It took a long time for Michaels and Hart to bury the hatchet, both outside of the ring and on WWE television.