#4 Sheamus
Sheamus returned to WWE last month as a heel with his old menacing look. The Celtic Warrior and The Big Dog are no strangers to each other. By eliminating Reigns, Sheamus will come out looking strong, especially since he has been away for some time.
Both Superstars are on the same brand as well, so a short rivalry between the two before 'Mania can't be ruled out. Although Sheamus isn't currently listed as a participant for the Rumble match, there's no reason why he won't take part.
#3 Drew McIntyre
Drew McIntyre is another Superstar who's had an issue with Roman Reigns in the past. The two stars faced off at WrestleMania 35 last year where Reigns came out victorious. The Scottish Psychopath has been tearing through his opponents lately and he is one of the favorites to win the 2020 Royal Rumble match.
McIntyre winning the Rumble would be a great achievement for him and doing so by eliminating Reigns would be a bonus. 2020 could be McIntyre's year, and it could all start with him eliminating a certain top babyface.