#3 AJ Styles
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Today, 'The Phenomenal' AJ Styles is enjoying his second reign as WWE Champion, and it is quite hard to imagine what WWE would have been like for the past two and a half years without him.
At one point, however, AJ Styles in WWE is something that everyone, including WWE and AJ themselves, thought would never ever happen. Before leading the Bullet Club in NJPW and Ring of Honor, AJ Styles was Mr TNA. AJ was a five-time World Champion in TNA, which was a three-time NWA Champion, and two-time TNA. He also held every other Championship in company history that had been introduced during his 11 + years with them.
Styles was to TNA what The Undertaker was to WWE and Sting to WCW, that is until he left the company in early 2014.
And even then, there was no talk whatsoever of 'The Phenomenal One' ever joining WWE. With AJ being the modern day Shawn Michaels, his talents was something WWE could not overlook anymore and in January 2016, AJ Styles signed with WWE and debuted to a monster pop, at the Royal Rumble. He is now a two-time WWE Champion, two-time WWE United States Champion and has wrestled some of the best WWE matches, ever.