Then I leave it up to you... I atone for my crime by doing so...
Emperor Cain is known as the first human to be born on the planet along with Miang and the Gazel Ministry. He was pre-programmed from creation to carry out the will of Deus and constantly work towards his revival. His mind was always focused on protecting humanity until the time of "the Gospel" when Deus would be revived using all of humanity as spare parts. He was instrumental in creating all the myths, legends and religions of the world what would be used to keep humanity under his and the Ministry's control. Though Abel, the boy who survived the crash landing of the Eldridge and the first Contact, now grown into a man knew the truth of the matter and began to speak out to the planet's burgeoning human population against Cain and the Ministry's lies and sowed the seeds of a rebellion among the Lambs. Cain killed Abel and the original Elhaym to silence them, though the murder plagued his conscience and because of it he developed a guilt-driven sympathy for normal surface dwelling Humans, in effect breaking free of his programming to a degree. He served as the Emperor of Solaris and the de factor ruler of all life on the planet. A long time after the end of the Shevat-Solaris War, Cain reached out and contacted Krelian and Miang at the Ministry's urging. They saw Krelian as a key asset in their grand plan so Cain came to Krelian and offered to help him achieve his goals if he would help them achieve theirs. Krelian agreed and he forged an alliance of mutual dependence with one another. However while Cain was sincere about coming to Krelian for his help to save his "children", the Ministry was not. Instead, they were looking to condemn humanity to death as a biological patch kit for their so-called god. As payment for his help, Krelian performed an extensive procedure on Cain in order to extend his life indefinitely. Cain's coffin-like suit, mask, throne, and a good portion of the Imperial Palace in Etrenank was used to just keep him alive. He was once a strong ally of Miang and the Gazel Ministry, though his actions over the many years caused a split between the Emperor, Miang and the Ministry. Cain was concerned for the general well-being of all life while the Gazel were only interested in themselves and Miang was only concerned about Deus. He was assassinated by Kahran Ramsus, a clone of Cain created by Krelian intended to be an artificial -Contact- in the year 9999 after Eldridge's crash. Ramsus was manipulated into doing so by Miang at the behest of the ministry. Cain's death allowed Miang and the Gazel Ministry to use the Gaetia Key to raise Mahanon, the main hull of the Eldridge, from the ocean floor and turn the better majority of the world's population into -Wels- who would then be absorbed into Deus. Cain originally sent Citan Uzuki to the surface in order to keep a constant vigil on Fei Fong Wong, the actual -Contact- after he was brought to Lahan by Wiseman. Cain and Citan communicate via a telepathic link several times over the course of the game and Citan keeps the Emperor abreast of all the recent things happening around Fei and his group.
Cain's face is never shown beyond the orange skull-like mask used to keep him alive. However it is stated in Perfect Works, that while he would look similar to Ramsus, it wouldn't be exact since Ramsus' appearance was altered by his fusion with the original Kahran.