#4 Samoa Joe
As a child, Samoa Joe was a Junior Judo State Champion in California. Later, he became more interested in Brazilian jiu-jitsu.
He extensively used many BJJ techniques while fighting inside the squared circle. He had a sick rear naked choke and one of the best armbars in the game.
He made good use of Judo throws to take down his opponents and later strangulate the living soul out of them with his ground game.
Samoa works on his striking aspects like kickboxing and Muay Thai also. He prefers to train at his home gym mostly.
If you watch his fights closely, it's easy to spot the components of Jiu-jitsu in his moves.
Had he polished his skills and invested more time in it, Samoa could have made an equally good career in MMA.
But he chose to belong in the squared circle.