The Ultimate Fighting Championship held its very first event on Nov. 12, 1993, in Denver, Colo. The event featured fighters from various martial art styles from around the world all coming together to see which was most effective in a real combat situation. In the beginning there were no weight classes, no rules, and no steroid testing. It was no-holds-barred action at its finest featuring the biggest baddest martial artists on the planet — and one small skinny Brazilian who changed the world. Here’s a look at the top 10 UFC stars from the early days.

10. Mark Kerr

Mark Kerr was a Division I collegiate wrestling champion who made the transition to MMA with the help of his longtime friend and training partner Mark Coleman. He made his MMA debut in Brazil in Jan. 1997 where he won the World Vale Tudo Championship 3 heavyweight tournament, winning three fights in one night. Six months later he would make his highly anticipated debut in the Octagon by winning the UFC 14 heavyweight tournament. He went on to repeat that performance by also winning the UFC 15 heavyweight tournament, defeating two opponents that night with a total fight time of 70 seconds! They didn’t call him “The Smashing Machine” for nothing and the 2003 HBO documentary of the same name takes an unforgettable look into who this MMA warrior was.

9. Keith Hackney

Keith Hackney is an Illinois native and entered the UFC with black belts in Kenpo Karate, Taekwondo, and Tang Soo Do. Hackney only won two fights inside the Octagon but they were so unforgettable that he has forever been immortalized in early UFC highlight reels. In Sept. 1994 a roughly 200-pound Hackney faced the six-foot eight-inch 600-pound sumo wrestling giant Emmanuel Yarbrough at the UFC 3 open weight tournament. The size difference was phenomenal but Hackney attacked the giant quickly and knocked him down with a palm strike. Yarbrough got back to his feet and pushed Hackney through the cage door, but when the bout restarted Hackney smashed the giant with a flurry of punches to the top and back of the head which forced the referee to stop the match. Due to an injured hand Hackney was unable to continue in that night’s tournament but fought at UFC 4 three months later where he faced taekwondo black belt Joe Son. During the bout Hackney delivered such a barrage of punches to Joe Son’s groin it’s amazing his testicles weren’t turned into complete mush. Once you see it you can never forget it.

8. Randy Couture

Randy Couture was a former Greco-Roman wrestling champion and NCAA Division I All-American collegiate wrestler. “The Natural” made his Octagon debut in May 1997 where he fought two opponents in one night and beat them both in a total of just over 3 minutes to win the UFC 13 Heavyweight Tournament. Couture returned in October ’97 and scored a TKO win over Vitor Belfort in a Heavyweight title eliminator bout. Then just two months later Couture took on Maurice Smith at UFC Japan where he won a hard fought decision for the Heavyweight Championship. Couture would go on to have one of the most decorated careers in MMA history winning both the UFC light heavyweight and heavyweight titles multiple times.

7. Tank Abbott

Tank Abbott was one scary dude. The Huntington Beach native was known as a “Pit Fighter” who polished his fighting skills in bar fights. Although he had a wrestling background and in fact was an NCAA All-American, he preferred battering his opponents with fists. More of a street fighter than a technician, Tank made his Octagon debut at UFC 6 in July 1995 where he won his first two tournament bouts by knockout in just 2 minutes 11 seconds. His first fight that night lasted only 18 seconds! Tank would continue to fight in the UFC for years to come. He never really won a championship or even beat any really big names, but it was his attitude and aggression, his street fighter mentality, and that crazy look in his eyes that really made him an early UFC icon.

6. Vitor Belfort

Vitor Belfort burst onto the MMA scene with flying fists of fury. “The Phenom” began boxing at an early age and also studied BJJ under the tutelage of Carlson Gracie, who eventually awarded him his black belt. Belfort made his Octagon debut in Feb. 1997 where he defeated Tra Telligman and Scott Ferrozzo both via TKO in a total fight time of just 2 minutes to win the UFC 12 Heavyweight Tournament. At only 19-years-old Belfort became the youngest fighter to ever win a match inside the Octagon. The following years Belfort would go on to score a TKO victory over Tank Abbott, a submission win over Joe Charles, and a TKO over Wanderlei Silva before heading off to fight in the Japanese PRIDE organization in 1999. It was Belfort’s punch speed, aggression, and power that most people remember and he’s another one that went on to have a legendary career inside the UFC Octagon even winning the light heavyweight title in a rematch against Randy Couture in 2004.

5. Don Frye

Don “The Predator” Frye was a collegiate wrestler and professional boxer before he entered the MMA arena. Frye made his Octagon debut in 1996, winning the UFC 8 and the Ultimate Ultimate ’96 Tournament both in his first year of competition. Also that same year he made it to the finals of the UFC 10 tournament before losing to Mark Coleman. “The Predator” showed himself dangerous on the ground and on the feet, scoring finishes in 10 of his first 11 UFC matches — five by submission and five by knockout. He was truly a mixed martial artist who was known for his manly mustache and having a striking resemblance to the actor Tom Selleck. In fact Frye went on to appear in several movies himself.

4. Dan Severn

Dan “The Beast” Severn was a decorated freestyle wrestling champion and two-time Division I All American at Arizona State University. He also trained in Judo and Sambo before taking his fighting skills to the Octagon at UFC 4 in 1994. Severn would use submissions to finish his first two opponents that night before getting submitted himself in the tournament finals by the great Royce Gracie. Severn returned the following year to win the UFC 5 tournament and win the Ultimate Ultimate ’95 Tournament. And then in 1996 he avenged his only other loss, against Ken Shamrock, to win the Superfight Championship at UFC 9. And then Severn returned to the UFC the following year to fight Mark Coleman for the inaugural UFC heavyweight title. Severn went on to compete in MMA all the way until 2012, finishing his career with a truly remarkable record of 101-19-7.

3. Mark Coleman

Known as “The Hammer” and “The Godfather of Ground and Pound”, Mark Coleman was a 1992 Olympian and NCAA Division I Champion freestyle wrestler for Ohio State. At his first Octagon appearance in 1996, Coleman defeated Moti Horenstein, Gary Goodridge, and Don Frye in a single night to win the UFC 10 Tournament. He returned a few months later to win the UFC 11 Tournament, and then just a few months after that he won the inaugural UFC Heavyweight Championship by submitting Dan Severn at UFC 12 and a legend was born. Coleman went on to win the PRIDE 2000 Openweight Grand Prix and even returned to the Octagon at UFC 100 in 2009 to score a win over the late great Stephan Bonnar. The early Coleman was as jacked and as brutal as they come and his work in the cage will never be forgotten.

2. Ken Shamrock

Ken Shamrock began his mixed martial arts career fighting for the Pancrase hybrid wrestling organization in Japan. After finding success there he was destined to be one of the stars of the early UFC. Making his Octagon debut at UFC 1 he first scored a 1:49 heel hook submission over Patrick Smith before getting introduced to the rear-naked choke of Royce Gracie in the tournament finals. After another stint in Japan Shamrock returned at UFC 3 in Sept. 1994 where he won his first two fights of the night but had to withdraw from the finals due to injury. Then in April 1995 Shamrock took part in UFC 5 and became the first person ever inside the Octagon who did not lose to Royce Gracie. He didn’t beat him either, but he didn’t lose. The two fought for 36 full minutes and finally declared a draw. Shamrock returned at UFC 6 to win the inaugural Superfight Championship by submitting Dan Severn in just over 2 minutes.

1. Royce Gracie

The undeniable mixed martial arts legend Royce Gracie put the UFC and Gracie Jiu Jitsu on the map. He showed the world that a smaller man could beat much larger and stronger opponents with proper grappling techniques. Beginning with UFC 1 in 1993, Royce fought three times in one night defeating Art Jimmerson, Ken Shamrock, and Gerard Gordeau, all by submission with a total fight time of less than five minutes! Incredible. And at UFC 2 the following year he beat four opponents in one night! He went on to compete at UFC 3, UFC 4, and UFC 5, all without taking a defeat. In fact the early UFC days were little more than a prolonged Gracie Jiu Jitsu infomercial and Royce was the star of the show. And the rest, as they say, is history.