The Royal Rumble is one of the pay-per-view events organized annually by WWE, the fourth longest running among those proposed and one of the most important, so much so that it is commonly referred to as one of the so-called Big Four, together with WrestleMania, SummerSlam and Survivor Series . The name of the event and its notoriety derive from the type of main match that characterizes it, namely the 30-man royal rumble match (20 in the inaugural edition of 1988 and 40 in the 2011 edition). Starting with the 1993 Royal Rumble, the winner earns the right to challenge the world champion to a match at WrestleMania. 30 wrestlers participate in the match (20 in the inaugural edition, 40 in the one in 2011), but at the beginning there are two in the ring. The remaining twenty-eight reach the square at predefined time intervals (normally every 90 seconds), according to a previously drawn order. The match is won by whoever remains alone in the ring once the entrance phase is over. A wrestler can only be eliminated if he ends up outside the ring by stepping over the top rope and touching the ground with both feet; he cannot be defeated either by using submission holds or by using the pin.
Since the subdivision of the WWE fighter park into two different rosters (Raw and SmackDown!) was established, the Royal Rumble became one of the few appointments where athletes from both shows met. From 2003 to 2006, 15 wrestlers from Raw and 15 from SmackDown! took part in the brawl royal. From 2007 to 2010, with the addition of ECW as a new brand, a change was made to the number of entries: 13 wrestlers from Raw, 10 from SmackDown! and 7 of the ECW. The roster split also meant that the winner of the royal rumble match would have to wrestle their show's world champion at WrestleMania. However, in 2004 a new rule was instituted that allowed the winner of the royal fight to choose the champion he wanted to face at WrestleMania. This allowed Chris Benoit, winner of that year's edition, to switch from SmackDown! on Raw to fight Triple H, the holder of the World Heavyweight Championship. The rule that provides that the winner of the Royal Rumble match earns the opportunity to challenge the world champion at WrestleMania was established in 1993, with two exceptions, in the 1992 edition and in the 2016 edition, when victory guaranteed the conquest of the world title.