The Royal Rumble match is traditionally one of the most chaotic, unpredictable matches of the calendar year.
While the winner of the huge 30-man over-the-top-rope Battle Royal may not be in great doubt most years, the surprise entrants, outstanding and unexpected performances and emotional returns have captivated audiences for the better part of 27 years.
Everyone from Hulk Hogan to Bob Backlund to Bret Hart and John Cena have supplied fans with moments and performances that have defined the event.
This year's event, emanating from the Consol Energy Center in Pittsburgh, is sure to be no different.
Superstars such as the aforementioned Cena, Daniel Bryan, CM Punk, Randy Orton, The Shield and the Wyatt Family are certain to make their impact felt. What surprises will they and WWE have in store for fans in the Steel City, and where will those moments rank among the greatest of all-time?
Only time will tell.
In preparation for the first stop on the road to WrestleMania, here is a look back at the biggest surprises in Royal Rumble history.
The surprises are listed chronologically. Feel free to express your views as to which surprise is the greatest in Royal Rumble history in the comments section below.
In 1989, Hulkamania was still running wild in World Wrestling Entertainment. Hulk Hogan was the unquestioned top babyface in all of professional wrestling and seemed like a shoo-in to win the Royal Rumble match, which would be broadcast on pay-per-view for the first time ever that year.
Fans paying their money and tuning in to see The Hulkster's latest triumph were disappointed when he was the 21st Superstar eliminated from the Rumble match at the hands of the Big Boss Man and Akeem, known collectively as the massive Twin Towers.
The elimination made sense within the context of storylines as Hogan had been feuding with the gargantuan Superstars. In the weeks that would follow, Hogan would dispatch of his rivals and end the feud in impressive fashion en route to an outstanding WWE title match against Randy Savage at WrestleMania V.
2004 Hall of Famer Big John Studd would win the 1989 Royal Rumble in what would stand as one of his most memorable moments. Still, fans struggled to believe that former WWE champion Hogan had lost a high-profile pay-per-view match.
In the middle of the 1990 Royal Rumble match, Ultimate Warrior entered the squared circle and began dominating his competition, as had expected. Four entries later, Hulk Hogan stepped into the ring and the crowd excitement swelled to a fever pitch.
Hogan dumped "Superfly" Jimmy Snuka and Haku over the top rope while Warrior eliminated Shawn Michaels and Rick Martel.
Then it happened.
The two most popular Superstars in WWE stood face to face in a showdown that, unbeknownst to fans, would tease a truly epic WrestleMania VI main event.
The marquee stars would crash into one another with shoulder blocks before the arrival of the Barbarian brought their brief encounter to an end.
An inadvertent clothesline from Hogan to Warrior would result in the elimination of the Intercontinental champion Warrior and the emphasis for one of the biggest matches in WWE history.
Warrior would go on to win the incredibly rare babyface versus babyface match and capture the first, and only, WWE Championship of his career.
The showdown between he and Hogan in the Rumble match was one that fans had never expected and, after witnessing it, would never forget.
Bob Backlund is one of the greatest Superstars in WWE history. He reigned as the promotion's heavyweight champion for five years and defeated legendary stars during his time on top, including Greg "the Hammer" Valentine, the Wild Samoans, "Superfly" Jimmy Snuka and "Superstar" Billy Graham.
His championship reign would come to an end in 1983 with a controversial loss to the Iron Sheik. The Division II NCAA wrestling champion would depart from the Vince McMahon-owned company shortly thereafter.
His return to WWE in 1993, at a time when the company was moving in a more youth-oriented direction, was a shock to many.
His performance in that year's Royal Rumble would be even more surprising.
Entering the match at No. 2 and lasting until the final three competitors, Backlund would be eliminated by eventual winner Yokozuna after one hour, one minute and 10 seconds of competition.
It was the beginning of a career renaissance for Backlund that would see him turn heel, portray a fresh, original, psychotic character and stun the wrestling world by capturing his second WWE Championship.
His performance in 1993 confirmed every story ever told about his unrivaled physical fitness and proved that a Superstar from another generation could still capture the attention of modern-day fans.
In 1994, Bret Hart and Lex Luger were not just simply vying for the right to challenge Yokozuna for the WWE Championship at WrestleMania X—they were also vying for the title of most popular Superstar.
Despite being shuffled to the background in favor of physical specimen Luger, Hart's connection with the audience proved to be too much for the massive marketing machine Vince McMahon's company had put behind the former NWA World Heavyweight champion. Soon, Hart had overtaken Luger in popularity, but not significantly.
As that year's Royal Rumble kicked off, Hart and Luger appeared to have equal chances of winning and earning the future title opportunity.
Few could have guessed just how equal those chances actually were.
The final four of the '94 Rumble featured Hart and Luger, the rapidly improving Shawn Michaels and tag team specialist Headshrinker Fatu. Luger and Hart dispatched of those two Superstars and then thrilled fans by going at it.
In a shocking, controversial moment, both men tumbled over the top rope, landing on the arena floor at the same time.
Officials, including WWE president Jack Tunney, struggled to make a ruling on the situation. Eventually, it was determined that both Hart and Luger had won the match, making it the first and only time in WWE history that there have been co-winners of the Royal Rumble match.
Both men would go on to have matches against Yokozuna for the WWE Championship at WrestleMania X, with Hart being the Superstar to end the lengthy reign of the massive competitor.
For many years, the Royal Rumble was a match that did not favor a Superstar entering early in the bout and realistically having a shot at winning the whole thing.
That forever changed in 1995, when Shawn Michaels entered the match at No. 1 and proceeded to make history.
He, along with No. 2 entrant "British Bulldog" Davey Boy Smith, outlasted 28 other Superstars en route to becoming the final two competitors vying for the right to go to WrestleMania XI and challenge for the top prize in all of professional wrestling, the WWE Championship.
At one point, Smith caught Michaels with a big clothesline and sent him over the top. Fans rejoiced as the popular Englishman had picked up the biggest win of his career just months after returning to the promotion.
Unfortunately for him and those fans, Michaels grasped onto the top rope and never allowed both feet to touch the floor. He pulled himself back into the squared circle and, as Bulldog celebrated the win on the ropes, the Heartbreak Kid struck him from behind and knocked him to the arena floor, winning the first of two Royal Rumble matches.
Michaels would go on to lose his title match to Diesel at WrestleMania XI but would rebound, winning the following year's Rumble match and defeating Bret Hart at WrestleMania XII to capture his very first WWE Championship.
The 2001 Royal Rumble featured one of the greatest individual performances in World Wrestling Entertainment history, as the Big Red Monster, Kane, entered the match at No. 6 and lasted for 53:46.
He would eliminate a record 11 Superstars, including favorite The Rock, before being the final competitor eliminated.
"Stone Cold" Steve Austin would become the first Superstar to win the Rumble match three times, but it was the performance of Kane that would have fans buzzing the following morning. In fact, he was booked so strong throughout the match that many thought it was the beginning of a huge renewed push for him.
That would not be the case. Instead, Kane's performance in 2001 remains one of the great stand-alone performances in event history.
Backtracking a bit, a surprise entrant made his return to the company for one night only, entering the Rumble match at No. 12. The greatest Intercontinental champion of all time, the Honky Tonk Man, shook his hips and sang his theme song while Kane watched on, both confused and amused.
Having heard enough from the Memphis native, the Big Red Monster blasted him with his own guitar and sent him over the top rope for the elimination.
While 2000 featured a surprise return in the form of Bob Backlund, 2001 was the first year where surprise returns became a staple of Rumble matches.
In October of 2007, John Cena suffered a torn pectoral and was expected to miss anywhere from six months to one year, ensuring that he would not participate in either the Royal Rumble or WrestleMania pay-per-view events.
Fast forward to January and the Royal Rumble's return to Madison Square Garden.
With the likes of Triple H, Batista, Umaga, Undertaker and Shawn Michaels slated for the match, that year's Rumble match was shaping up to be one of the most star-studded in recent history.
"The Game" was the odds-on favorite to win the match and head to WrestleMania XXIV to challenge Randy Orton for the WWE Championship.
Then, the buzzer sounded signaling the arrival of the 30th and final entrant in the match. The familiar sound of "My Time is Now" played, and the hardcore fans inside the hallowed halls of MSG erupted into a huge ovation as Cena made his unexpected return to action.
That huge pop he received upon his entrance gave way to typical jeers and "Cena sucks" chants.
Just over eight minutes later, Cena delivered the Attitude Adjustment to Triple H over the top rope and scored one of the most unlikely wins in Royal Rumble history.
He would go on to lose his WWE title opportunity at WrestleMania when Orton defeated both he and Triple H in a Triple Threat match, but his surprise return to the company stands as one of the loudest ovations in Royal Rumble history and one of the legit unexpected surprises in the annals of WWE.
The 2010 Royal Rumble match was one of the best in company history. It featured several different stories woven throughout the nearly 50-minute match, one of the best coming early on and involving CM Punk.
The leader of the Straight Edge Society eliminated Superstar after Superstar, all the while promoting the beliefs of his cult-like faction.
That ended when the massive Great Khali entered the bout and provided Punk with his first major challenge. Before the first-ever Indian-born World Heavyweight champion could do too much damage to the future Best in the World, Beth Phoenix entered the match at No. 6 and used her feminine ways to eliminate Khali, applying the dreaded liplock and pulling him over the top rope.
She then exploded with some hard-hitting offense to Punk before falling victim to the GTS and being eliminated.
Phoenix's involvement in the match was both unexpected and short, but the Buffalo native made the most of her opportunity, delivering a memorable performance.
Two years later, WWE would copy the formula, adding Kharma to the Rumble match and allowing her a hot minute or two to pop the audience and bump around a guy before being eliminated.
The 2011 Royal Rumble was the biggest in WWE history, at least from a size perspective.
For the first time, 40 Superstars entered the match, all with their sights set on earning a WWE or World Heavyweight Championship match at WrestleMania.
With an expanded field of competitors, it opened up the possibility for more surprise entrants.
Booker T's return surprised fans early in the match, but it would be the arrival of another Superstar that delivered the most memorable moment of the contest and featured one of the loudest pops of the evening.
The revving of a diesel engine sounded throughout the TD Garden in Boston and the fans erupted with a huge ovation as Kevin Nash, with his hair dyed jet black, stepped through the curtain and into the arena.
With chants of "Diesel" filling the arena, he took the fight to some of the youngest, brightest Superstars on the roster before being dumped over the top rope by Wade Barrett.
The return and his stint in the Rumble match was short-lived but Nash's performance as Diesel proved that nostalgia will always hit with longtime, hardcore wrestling fans.
Dolph Ziggler was arguably the best wrestler on the roster when the 2013 Royal Rumble kicked off from the US Airways Center in Phoenix, especially considering CM Punk's injuries and Daniel Bryan primarily functioning as a tag team wrestler.
As such, it made sense that he would enter the Royal Rumble at No. 1 and be the workhorse of the match.
The audience, both in attendance and watching around the world, would be absolutely stunned by the Superstar who would join him to start the match.
"Break the Walls Down" would explode over the PA system and Chris Jericho made an absolutely unexpected return to World Wrestling Entertainment, five months after losing a "Loser Leaves WWE" match against Ziggler at SummerSlam.
The two talented in-ring competitors would last over 45 minutes before Ziggler dumped Jericho, to the disappointment of the Phoenix fans.
Jericho's return would prove that, in the age of the Internet, it was still possible to carry out surprises that shocked and thrilled fans across the globe.
Y2J would follow up his performance by appearing in an Elimination Chamber No. 1 Contender's match in February before feuding with newcomer Fandango heading into WrestleMania 29.