The Undertaker is perhaps the greatest and most decorated superstar in the history of WWE, and fans have been fortunate to witness plenty of timeless matches throughout his career. He's gone toe to toe with other wrestling icons such as Shawn Michaels, Hulk Hogan, The Rock, Kane, Ric Flair, Triple H, John Cena, Edge, Kurt Angle and Steve Austin, among many others.

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In some ways, it feels as though Undertaker's career is more than complete -- that he's basically put on all the dream matches we've wanted. But believe it or not, The Phenom never squared off one on one with these 9 wrestling legends.

10 Lex Luger

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The Undertaker and Lex Luger faced off at The Great American Bash 1990, but this took place when the former was in his 'Mean' Mark Callous gimmick. He simply wasn't an established main event star at the time, so it really didn't have the feel of a "dream" match.

Undertaker joined WWE later that year, while Luger would join the promotion in 1993. Of course, Vince McMahon started pushing Luger as his new main face following Hulk Hogan's departure. A match with Undertaker then could have been something special. Their showdown in WCW was simply three year too early.

9 Ricky Steamboat

The WWE Hall of Famer spent the bulk of his prime years in NWA and the AWA. He briefly worked with WWE from 1985 to '88, but this was well before The Undertaker joined WWE in 1990.

Steamboat would later return to the WWE for one year in 1991, but he didn't ever go up against The Undertaker. It's been suggested that Steamboat was actually supposed to be squashed in a match against The Deadman, but he refused. Steamboat would return to WCW in 1992, all but ending the chance of a dream showdown against Undertaker.

8 Bob Backlund

Before Ric Flair, Hulk Hogan and Randy Savage took over as the main faces of professional wrestling in the '80s, Bob Backlund was Vince McMahon's go-to star in the '70s. However, Backlund left the WWE in 1984 - six years before Undertaker would debut in the company.

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Backlund returned to Vince's promotion in 1992, but he entered a lengthy feud with Bret Hard and thus never squared off against The Undertaker. As Undertaker began to rise to main event status, Backlund was only wrestling part-time. The dream match between these two icons just wasn't meant to be.

7 Andre The Giant

By the time Undertaker entered the WWE, Andre the Giant's historic reign with the company was slowly coming to an end. His iconic feud with Hulk Hogan was long gone, and Vince McMahon was starting to transition towards new faces.

Andre would leave WWE in 1991, and he sadly passed away two years later at the age of 46. Fans can only wonder what a showdown would have looked like between he and Undertaker -- two of the most dominant and indestructible forces in the company's history. All we know is that it would have been a sight to behold.

6 Sergeant Slaughter

Sgt. Slaughter returned to WWE in 1990 after five years with the AWA. He was present during The Undertaker's early days in WWE, and there were more than enough opportunities to pit these two future legends against one another. Instead, Sgt. Slaughter entered a feud with Hulk Hogan, whom Undertaker would eventually feuded with in 1991.

The only time Undertaker and Sgt. Slaughter shared the ring was at the 1992 Royal Rumble, won by none other than Ric Flair. Of course, Undertaker wasn't quite an established main event talent in the early '90s, while Sgt. Slaughter was being pushed as one of the company's main heels.

5 Eddie Guerrero

The Undertaker and Eddie Guerrero were involved in a couple of tag team matches, but there was never a one-on-one showdown between the two. At best, both legends took part in a fatal four-way match (also involving JBL and Booker T) for the WWE Championship at Armageddon.

The match was ultimately won by JBL, who retained his championship. At least we got to see Guerrero vs. Undertaker in some form, even if it wasn't a singles match. Guerrero tragically passed away at the age of 38 on Nov. 13, 2005.

4 Dusty Rhodes

"The American Dream" enjoyed an illustrious career that spanned three decades. Rhodes (the father of Dustin/Goldust and Cody Rhodes) was a legend in NWA, WCW, and WWE - where he competed from 1989 to '91. The Undertaker-Rhodes dream match didn't happen due in large part to the fact that the latter wasn't around in WWE for very long.

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If Vince McMahon managed to keep him around past 1991, maybe The American Dream would have gone up against The Undertaker at some point. For what it's worth, Undertaker did go up against Goldust four times in 1996. At least we got to see him go up against one member of the legendary Rhodes family.

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2 'Macho Man' Randy Savage

The Undertaker joined Jake Roberts' scheme in ruining Randy Savage's storyline wedding with Miss Elizabeth by placing a snake in one of the wedding presents. The Phenom would attack Savage moments later, but this never actually led to a match between the two.

Following a brief alliance with Roberts, Undertaker turned on his friend when "The Snake" tried harming Miss Elizabeth. This led to a feud between Undertaker and Roberts, and Savage eventually transitioned towards a commentary role. He left WWE in 1994 so that he could continue in-ring action by signing with the WCW promotion.

The Macho Man vs. The Undertaker. What a showdown of two wrestling GOATS that would have been!

1 Sting

It should be noted that Sting and The Undertaker squared off at a WCW show in 1990, but that took place during his aforementioned 'Mean' Mark Callous gimmick. It's also important to note that Sting was also in his "Surfer" gimmick at the time. Really, the dream match everybody wanted was Crow Sting vs. The Undertaker, i.e. the gimmicks everyone knows and loves the most.

The two superstars had so many similarities, but Sting was performing for WCW during the '90s, while Undertaker was competing on the other side of the Monday Night War. When WCW was bought out, Sting opted to sign with TNA instead of coming aboard to WWE. He finally joined Vince's promotion in 2014, and WrestleMania 31 marked the perfect opportunity to pit the two legends against one another.

Instead, Undertaker faced Bray Wyatt, while Sting clashed with Triple H. The Vigilante suffered a legitimate neck injury during his match against Seth Rollins at Night of Champions 2015, and it forced him into retirement. With that, fans unfortunately had to accept that Undertaker vs. Sting was never, ever going to happen.

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