The UFC has grown exponentially since its inception 30 years ago. The promotion has continued to evolve and grow its brand globally and today's announcement further proves that.The promotion's parent company, Endeavor, announced that they signed an agreement to form a merger between the MMA entity and WWE. The total valuation of the merger will make the new entertainment company worth over $21 billion.What made the merger more interesting is how much value the promotion has gained since Zuffa sold it in 2016. At the time, Endeavor purchased the MMA leader for $4.2 billion, which was well over the $2 million that Frank and Lorenzo Fertitta paid for when they took a chance on the promotion.Given Endeavor's latest valuation of the promotion, their investment has clearly paid off. They valued the MMA entity at $12.1 billion, which means that it has nearly tripled in value. They are committed to doing the same with WWE. During his appearance on CNBC, Endeavor CEO Ari Emanuel mentioned that he believes the sports entertainment powerhouse will be just as successful of an investment.He said:"We've tripled the ebidta in that period of time and now with this [WWE], this is gonna be UFC 2.0 as it relates to all the things in the flywheel that we could bring."Squawk on the Street@SquawkStreet$EDR has won the battle royal for $WWE, merging @WWE with @ufc in a $21 billion deal. @VinceMcMahon and @Endeavor CEO Ari Emanuel discuss with @ScottWapnerCNBC. McMahon: It’s the right time to do the right thing.Emanuel: We have unbelievably attractive economics.5827$EDR has won the battle royal for $WWE, merging @WWE with @ufc in a $21 billion deal. @VinceMcMahon and @Endeavor CEO Ari Emanuel discuss with @ScottWapnerCNBC. McMahon: It’s the right time to do the right thing.Emanuel: We have unbelievably attractive economics. https://t.co/t73lUcVEM7Conor McGregor congratulates Endeavor on the UFC-WWE mergerConor McGregor@TheNotoriousMMA @wwe, @ufc, @TheMacLife #itsinevitable526544114🇮🇪 @wwe, @ufc, @TheMacLife 🇺🇸 #itsinevitable https://t.co/4m75uwZr23Conor McGregor recently shared his thoughts on the UFC's merger with WWE.'The Notorious' is arguably one of the main reasons why the promotion's value has skyrocketed since Endeavor purchased it in 2016. He has set numerous records for pay-per-view buys and is undoubtedly the biggest star in both the promotion and the sport.The former two-division champion took to Twitter before the merger was confirmed and congratulated the MMA entity for their latest valuation and Endeavor for investing in WWE, writing:"Congrats to the @ufc now worth a cool Proper $12bn. Wow! Endeavor bout to scoop the @WWE now also. Incredible. What a powerhouse!"Conor McGregor@TheNotoriousMMACongrats to the @ufc now worth a cool Proper $12bn. Wow! Endeavor bout to scoop the @WWE now also. Incredible. What a powerhouse!182591057Congrats to the @ufc now worth a cool Proper $12bn. Wow! Endeavor bout to scoop the @WWE now also. Incredible. What a powerhouse!McGregor even got in on the fun and tweeted out a photoshopped image of himself holding both championships.