Dr. Cain

Dr. Cain (Dr. ケイン) is the scientist and archaeologist who found Mega Man X on April 14th, 21XX. X was in a capsule buried deep underground in the abandoned warehouse of Dr. Light's ruined lab. He created the Reploids based on X's design, being the first in November 22nd. As Cain couldn't fully understand X's design, and the Reploids didn't had a diagnostic like X, the Reploids could have problems and started to become "Mavericks" (Irregulars). The Maverick Hunters where founded to counter the Mavericks. Sigma, Dr. Cain's most advanced creation, became the leader of the Maverick Hunters. Cain Labs created Dr. Doppler and the Repliforce. Dr. Cain is not mentioned again after Mega Man X4, so it's popularly assumed he died of "old age".

In The Day of Σ, Cain has a life support to extend his life, with four tubes connect in his back.