Originally Posted by
Brandon Hanvey
The Royal Rumble is a yearly match held at the start of the year. It is what is called a battle royal match. There are different kinds of battle royals. Most involve a large number of wrestlers. The Royal Rumble usually involves 30 participants.
Unlike a typical battle royal where all the wrestlers start out in the ring, the Royal Rumble starts with only two wrestlers in the ring. Then every minute and a half another one of the 28 other wrestlers comes out and enters the match. This keeps happening until all 30 have entered. Wrestlers are eliminated by being sent over the top rope and both feet touching the outside ring floor. The winner is whoever is the last man in the ring once all 30 have entered and the rest eliminated. For the past few years, the winner of the Royal Rumble has received a shot at the top title in a match at Wrestlemania.
As for mystery opponents, they are basically unannounced participants. For the Royal Rumble, the WWE usually announces most of the 30 participants. They typically have a few slots that are open for "mystery opponents" These are used to keep the fans guessing as to who might win and to have some surprises/fun such as wrestlers have have shown up for a while (ie older wrestlers who have semi retired/left the company) or wrestlers who are returning from injury or time off.