A legendary wizard, Jeremiah Cain was an expert in the dark magic ways. Personally he trained under the guide of Mago, an extraordinary wizard. After the disapearence of Mago, (seen in Number of the beast), Jeremiah take his reponsabilities as wizard.
Jeremiah helped several times the Stormwatch operatives in cases of mystical nature, but he prefered dedicate his time to metaphysical studies and the exploration of the higher planes of reality. He also dedicated part of his tie to share his knowlegde to his pupil Betty.
After a psychic battle the spirit of Jeremiah was lost and wandered in th higher planes, uncapable to return to his body. Bettie take care of him in that time.
After the End of the World, Jeremiah was capable to return to his body. Whatever experience he lived in the higher planes in some way changed him. Now thirsty for power, Jeremiah tried to absorb the remaining magical power of the damaged spirit of the earth. Posing as an extradimensional being called Aeon, Jeremiah tricked the surviving WildCATs into helping him. But in Egypt he revealed himself, sure about his triumph. He aslo revelaed tha this was a plan to protect the remains of the earth from a mysterious threat coming to earth.
However Jeremiah miscalculated the power of the earth energies and the interference of the remaining heroes. When he tried to absorb the full power he was interrupted by Mago, who distracted his former pupil meanwhile he was attacked by Spartan, Hellstrike and Fuji who killed him.