Real Name: Thomas Samuel Eamon Cassidy
Occupation: Professional criminal
Identity: Publicly known
Legal Status: Citizen of Ireland with an international criminal record
Other Aliases: None
Place of Birth: Dublin, Ireland
Marital Status: Single
Known Relatives: Sean Cassidy (Banshee, cousin), Theresa Rourke (Siryn, cousin), Maeve Rourke Cassidy (cousin by marriage, deceased)
Group Affiliation: Frequent partner of the Juggernaut
Base of Operations: Mobile
First Appearance: X-MEN #99 (in shadow), #101 (fully seen)

History: Thomas "Black Tom" Cassidy was the heir to his family fortune and estate of Cassidy Keep in Ireland. However, he wagered both the fortune and estate on a throw of dice, and thereby lost them to his younger cousin, Sean Cassidy. Black Tom and Sean Cassidy were rivals for the love of Maeve Rourke, and Sean eventually prevailed and married her.

While still a young man, Black Tom Cassidy turned to crime as a way of seeking thrills. Discovering how much he like it, Black Tom decided to make crime his profession. At first he masked his criminal activities under the guise of being a soldier of fortune. As such, he roamed the world offering his services as a gun for hire, while pursuing his criminal activities as well. While imprisoned in a Third World jail for acting as a mercenary for revolutionary forces that were defeated, Black Tom Cassidy met a fellow mercenary, Cain Marko. Cassidy and Marko struck up a friendship, and Cassidy used his own mutant powers, which he had already discovered, to enable both of them to escape jail.

Sean Cassidy was assigned by Interpol to a top secret mission which required that he stay out of touch with his family for a considerable length of time. When he left on his mission, his wife Maeve was in her month of pregnancy, although neither Sean nor Maeve knew it at the time. Their daughter, Theresa, was born during Sean's absence. Maeve took the infant Theresa with her on a visit to her relatives in Armagh in Northern Ireland. While she was there, Maeve, an innocent bystander, was killed by an explosion caused by terrorists. No trace of Theresa was found by the authorities, and it was assumed that she too had been killed. However, Black Tom Cassidy had been present at the scene of the explosion and had secretly carried Theresa off with him. Knowing of his own and Sean's mutant powers (Sean Cassidy is the former X-Man known as the Banshee), Black Tom suspected that Theresa might herself develop superhuman powers, as she grew older. Moreover, Black Tom saw Theresa as the daughter he wished that he and Maeve could have had together. So Black Tom decided to raiseTheresa himself secretly. Those who knew that Theresa had been born decided not to inform Sean Cassidy that Maeve had had a daughter in order to spare him additional grief he returned and learned of Maeve's death.

Eventually Black Tom Cassidy was reunited with his friend Cain Marko, who had become the superhumanly powerful Juggernaut. Cassidy suggested they form a partnership for criminal activities, and this partner has profitable to both ever since. Cassidy forced Theresa, who had grown into adolescence and superhuman powers, to help them in their crimes, but her heart was never in a life of crime. While briefly in the custody of legal authorities, Black Tom gentlemanly exonerated Theresa of responsibility for here crimes, and wrote a letter to Sean explaining who Theresa was Black Tom escaped and Sean and Theresa were joyfully reunited. Today Black Tom and the Juggernaut both remain at large.

Height: 6 ft.
Weight: 200 lbs.
Eyes: Dark Blue
Hair: Black

Strength Level: Black Tom Cassidy possesses the normal human strength of a man of his age, height, and build who engages in moderate regular exercise.

Known Superhuman Powers: Black Tom is a mutant with the superhuman power to generate blasts of force or heat. He uses a wooden shillelagh (a kind of Irish cane) to help him project the blasts, since woods acts as a focus for his power. It is not known whether there is anything unusual about his shillelagh, or how well, if at all, he can use his power without focusing it though wood. No upper limit has yet been observed as to the power of the energy blast he can project. He can wreak considerable damage with the force blast, and can melt metal with focused heat blasts.