#4 Ronda Rousey
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Former UFC Champion, Ronda Rousey is the current Raw Women's Champion. Earlier this year, she debuted in the company and since then managed to remain as a threat to her opponent.
WWE is booking her very strongly and whoever comes into her way get dethroned by the Baddest Women on the Planet. However, she is a threat in real life too.
She is a former UFC Bantamweight Champion as well as a Judoka too. She has a good record of 12-2 in the MMA world. She successfully defended her Bantamweight Title for a total of 6 times. If we consider all her accomplishments in the UFC, then it's safe to say that she is one of the toughest women on the planet.
Did a WWE Hall of Famer predict John Cena's heelish ways long ago? More details HERE.