#3 Bobby Lashley

The current Intercontinental Champion has a background in MMA, which many fans in the wrestling world know about. Lashley has competed in 12 different MMA companies such as Bellator, StrikeForce, and Titan, and he has clearly made a name for himself.
Lashley competed in the Heavyweight division as he brought his wrestling style into the cage, and it turned out to be very useful as he has had 17 fights inside the cage with a win-loss record of 15-2. Lashley has won 4 of those matches via KO, as well as 8 matches by submission, and he also won 3 of those bouts by decision too.
Did you know a top WWE Superstar just wrestled outside the company? More details HERE
In April 2018, Bellator officials had made announced that Lashley was still under contract with them despite his return to the WWE. The possibility of Lashley returning to fight in the cage is clearly 50-50 as he seems happy in the WWE, but it definitely isn't something that should be ruled out.