In the early 2000s, wrestling was at the peak of its popularity - the Attitude Era was making millions for Vince McMahon, andhe had money to burn. He had already basically crushed the competition in the fake fighting industry, so the egomaniac CEO set his sights on bigger fish - the NFL.
Teaming with NBC, he created the XFL - the Xtreme Football League. Because spelling "extreme" without the "e" is a total 1990s move. Due to an already existing Xtreme Football League, McMahon and company couldn't ever use the full name, leading him to claim that it stoof for "eXtra Fun League."
Unlike the NFL, where all of the teams were owned by different entities, the XFL had everything under one roof. Some rule changes attempted to differentiate it from NFL play, such as replacing the coin toss at the beginning of the game with a scramble for the ball, removing extra point kicks, and instituting a "No Fair Catch" rule. After strong ratings for the opening games, the league withered and died, and was disbanded after the final game, which was referred to as "The Big Game at the End of the Season." Yeah, I think "Super Bowl" has a better ring to it.