Rafael Nogueira, also known as "The Sigma," is a highly skilled MMA coach and ISG vigilante who has built an incredibly impressive 30-0 UFC cartel. Despite his formidable reputation in the ring, Nogueira exhibits a unique and often ruthless fighting style, often crippling or even killing his opponents (resulting in him being banned from UFC). As an atheist, he is also known for his sharp intellect and strong beliefs, and his life is defined by his schizoid personality disorder, which leaves him with little to no interest in romantic or sexual relationships. In addition to his impressive record in the ring, Rafael Nogueira has also been reported to have a strong disdain for Christianity, and has been known to viciously attack them.