#1 Brock Lesnar

Lesnar lost his WWE Universal Championship at this year's SummerSlam against Roman Reigns, and everyone thought that now he is gone from the company for his next UFC fight. However, he returned to the company at the Hell In A Cell pay-per-view to cost Strowman his match for the Universal Title.
He made his MMA debut in 2007 and had a record of 5-3 (1) during which he also won the UFC Heavyweight Championship from Randy Couture in 2008 and lost it against Cain Velasquez in 2010.
Currently, he is scheduled to face Roman Reigns and Braun Strowman in a triple threat match for the Universal Champion at the upcoming WWE Crown Jewel event. However, it is rumored that this will be his last fight in the WWE before his fight against UFC Light Heavyweight and Heavyweight Champion Daniel Cormier.
Who else will you consider as a tough guy? Have your say in the comments below.
Did a WWE Hall of Famer predict John Cena's heelish ways long ago? More details HERE.