Long before Randy Orton was known as "The Viper" and "The Apex Predator," he was known as "The Legend Killer." To many WWE fans, the latter was most popular persona as it perfectly fit the young, brash, arrogant third-generation prospect that seemed destined for greatness.

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Although Orton has had many rivalries with major names such as John Cena, Triple H, and Ric Flair to name a few, there are two standout feuds from Randy's past that still hold strong today as the best of his career. The two names that stand out for lifting Orton to that next level would be Mick Foley and The Undertaker. But which was The Legend Killer's greatest rivalry?

10 MICK FOLEY: First Headline Rivalry

WWE Randy Orton Glaring At Mick Foley

In summer of 2003, Orton proclaimed himself "The Legend Killer" and first targeted Shawn Michaels. Although Shawn was an industry veteran and a future Hall Of Famer at the time, this rivalry did not escalate too much in intensity but it was competitive.

After Michaels, Orton teased a feud with Mick Foley which involved humiliating Foley and kicking him down a flight of stairs. Foley was retired from full-time competition and had earned legendary status by 2003. Orton being a nasty heel, brutalizing Foley began a months long feud through two major events and a violent concluding match.

9 UNDERTAKER: First Shot At Super Stardom

WWE Undertaker Sitting Up In Front Of A Posing Randy Orton

Randy Orton began his iconic rivalry with The Undertaker in early 2005. Months prior, he had won the World Heavyweight Championship for the first time and became the company's then-youngest world champion. Although this was a great opportunity, it did not push Orton to superstardom yet. His rivalry with Undertaker gave him that push.

By 2005, Orton had feuded with Shawn Michaels, Mick Foley, Ric Flair, and Triple H. As impressive as all these names are, The Undertaker surpassed all of them as being the gatekeeper to greatness. Orton being paired up with arguably the industry's most legendary wrestler for the time showed that WWE had plans and faith in Orton.

8 MICK FOLEY: Significant WrestleMania Debut

WWE Randy Orton Tagging In Ric Flair In A Tag Match With Batista Against Mick Foley

WrestleMania is a big night for all WWE wrestlers and everyone remembers their first. Not everyone has a great or memorable debut and not everyone gets a big role on the show. Orton's WrestleMania debut was against Mick Foley with very big company.

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Orton, Ric Flair, and Batista defeated Foley and The Rock at WrestleMania 20 in March 2004 with Randy scoring the pinfall on Foley following an RKO. Although the match did not live up to expectations, it still put Orton on a big stage with two very big names for his first match on WWE's biggest night. It was a big moment and win for "The Legend Killer."

7 UNDERTAKER: Consideration To Break "The Streak"

WWE Randy Orton And Undertaker Staring Off In The Ring

Randy Orton's second match at WrestleMania was at one point discussed to have a major result. Although it has been long broken now, Orton was the first wrestler to end Undertaker's WrestleMania undefeated streak at WrestleMania 21 in April 2005.

This was teased when Orton shockingly reversed Taker's Chokeslam into an RKO which received a tremendous crowd response. The end result as we know was Randy becoming another victim in "the streak." Orton disclosed in his episode of WWE Untold on WWE Network that he was unprofessional before the match and is grateful he did not blow it.

6 MICK FOLEY: Introduction To Singles Specialty Matches

WWE Mick Foley Striking Randy Orton

Not counting the Handicap match at WrestleMania 20, Randy Orton was involved with Mick Foley in two specialty matches throughout their rivalry. Although the first was not a singles match, their first official battle was in January 2004 in a 30-man match.

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Foley was a "surprise" entrant in the Royal Rumble match by incapacitating one of Raw's entrants in order to take their spot to confront Orton who was already in the ring as a participant. This was also Orton's first appearance in the Rumble and Foley made it a heated night for him. This was also Foley's first match since WrestleMania 2000.

5 UNDERTAKER: Has Encountered Caskets & Hell

WWE Randy Orton Dropkicking Undertaker

Similar to his Foley feud, Orton had two specialty match encounters with "The Deadman." Their first meeting was at No Mercy in October 2005 with Randy and his father "Cowboy" Bob Orton defeating Taker in a Handicap Casket match. Following the match, Orton set the casket ablaze in an act reminiscent to Kane at the 1998 Royal Rumble.

Taker returned a month later for one of, if not, his greatest returns and one of the best moments in Survivor Series history. The culmination came the following month at Armageddon that December with Taker defeating Orton in a very underrated, overlooked and forgotten Hell In A Cell match that was heavy on bloodshed.

4 MICK FOLEY: Made Orton "A Man"

WWE Randy Orton Fighting With Cactus Jack

The prior Foley entry noted the second specialty match that the two had. In April 2004, Orton met Foley's most dangerous "face," Cactus Jack in a Falls Count Anywhere match at Backlash for Orton's Intercontinental Championship. In the build-up to their match, Foley warned Orton that he was going to "make him a man."

It was one of Orton's most violent fights of his career, complete with chairs, barbed wire, and thumbtacks. Orton's landing onto a sheet of thumbtacks made live fans and viewers cringe. Even after being thrown off the stage, Orton won the match after an RKO onto a barbed wire-wrapped baseball bat.

3 UNDERTAKER: Learned His Most Valued Lesson

WWE Matt Hardy And Randy Orton Staring At Each Other

In Orton's aforementioned episode of WWE Untold, he noted the most valuable lesson he learned of his professional career. During his Hell In A Cell match with Taker, Orton mentioned how during the match he was forewarned of an incoming "receipt" (a stiff strike in response to one received).

The "receipt" came in the form of a chair shot to the head, an attack that is now prohibited by WWE. Orton said that he was expecting all of Taker's force and power but received a luckier fate, a still strong swing but not to the full extent of strength. Orton said he learned from this that number one in wrestling is taking care of your opponent.

2 MICK FOLEY: Solidified "The Legend Killer"

WWE Randy Orton

Even though Orton pinned Shawn Michaels on numerous occasions in 2003, it did not fully solidify him as "The Legend Killer." It definitely put him on the right path and so did his encounter with legends sporadically on Raw.

With Orton pinning Foley at WrestleMania and then defeating Cactus Jack at Backlash, Orton won over many fans and critics that he was going to pay his dues and make a legacy for himself. Orton overcoming Foley was a landmark victory for Orton's career, making the "Legend Killer" persona a true reality.

1 UNDERTAKER: Lost The War, But Won A War

WWE Randy Orton Posing By A Flaming Casket

Even though Undertaker was the last man standing at the end of the Orton rivalry, Randy put up an incredible fight that many others have not been able to come close to. Taker won the war inside Hell In A Cell and won at WrestleMania 21, but Orton still scored a pinfall over Taker at SummerSlam 2005 and defeated Taker in his signature Casket match at No Mercy.

These two wins would have been monumental for anyone as it would have been for them, Orton received a major boost to his career following his time with Undertaker. Taker has suffered some questionable losses. But in hindsight, his losses to Orton were done in great faith and great care for the successful building of a future star.

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