#4 Randy Orton
Randy Orton is undoubtedly one of the most accomplished WWE performers of all time. A 15-year veteran of the company, he has been one of most consistent wrestlers of the last decade. But 2018 in particular has been pretty forgettable for The Viper, with no major storyline and championship run.
On May 18, WWE confirmed Orton had undergone successful surgery to repair a medial meniscus tear in his left knee, sidelining him for around 2-3 months.
There's a high possibility that Orton gets healed just at the time of SummerSlam. If it does happen, his return as a heel will be both shocking and enthralling.
Orton's best work has always come with a villainous gimmick, and with his current vanilla babyface run not being appealing, a heel turn would do wonders for his time ahead in WWE.