#4 Matt Hardy
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Matt Hardy had seemingly announced his retirement after an injury in 2018, but now there are rumors that he could appear at the Royal Rumble, just as his old tag team partner, Bray Wyatt, makes his return. The two of them teaming up could make for some fun.
Whether this is used to bolster the Raw tag team division in the long term or is just a one time thing remains to be seen, but Matt Hardy could have a lot of fun interactions with the likes of Aleister Black, John Cena, and the SmackDown personnel that we don't see him go up against.
Samoa Joe dealing with his bizarre persona could also be a potential standout on the night. Matt Hardy probably won't be a standout, but it will be fun to see him back in the fray, even if it might not be a long lasting thing.
Major rumor about recently released stars HERE