#3 David Arquette
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To be honest, I just think this one would be a whole lot of fun.
There are so many controversial figures in the history of professional wrestling, and not all are wrestlers, and some, have completely different professions. One such is the Scream movie series actor David Arquette. A lifelong wrestling fan, who was given the lead role in the dire but now cult classic WCW comedy film, Ready To Rumble, Vince Russo booked David to become WCW World Heavyweight Champion in 2000 to help promote the film and get some press.
The move is looked at as the final nail in the WCW coffin, and went down extremely bad with everyone, including Arquette himself, who only did it after he was begged by Russo and an unwilling Diamond Dallas Page.
Amazingly, David returned to wrestling as an actual wrestler, 18 years later in 2018. David wrestled Nick Gage in a Deathmatch at Joey Janela's LA Confidential, where he suffered a severe cut in the neck, causing him to bleed profusely.
David's performance in the match received critical acclaim. He is certainly earning his stripes in professional wrestling and a cameo appearance in the Royal Rumble makes total sense due to his celebrity status and how incredible he has been doing so far on the independent scene.
His appearance would also be surprising for everyone and provide a big pop and likely some comedic moments. Arquette recently appeared on an episode of WWE Backstage for a promo battle with Booker T, so we at least know WWE are willing to pick up the phone when it comes to him.