History
Growing up in a number of orphanages and foster homes in New Jersey, Sidney Green was a boorish, clumsy child, often the target of cruel bullying by children and adults alike. An inveterate bed-wetter, Green carried around with him the funk of uncleanliness, which further ostracized him and made him miserable. Green's attempts to curb his nightly emissions by avoiding liquids led to dizziness and dehydration. Once his mutation manifested, a blissful drought beneath the waist set in, and there was a lack of sodden sheets. When Green joined Xavier's he was put in Gambit's Squad. As a student at the Xavier Institute, Green had regained some confidence, forwarding audacious advances to aesthetically stirring female student Foxx. When Foxx was exposed as Mystique, Green sensed betrayal and attacked her. Within days, Green was able to walk again. Yet, the experience of being smashed in the head with a flush-lavatory triggered unfortunate memories of his childhood, perhaps permanently traumatizing him.[2]
M-Day

(Death)
Sidney retained his powers post M-Day and remained a resident at the school. Onyxx was critically injured by Reverend William Stryker during his attack on the institute and barely survived.
Onyxx was seen captured alongside his fellow students in Limbo.
Following the events of Messiah Complex, Onyxx joined the X-Men in San Francisco and was seen training with Colossus and Rockslide in Manifest Destiny.
Necrosha
During the attack of Selene's Inner Circle on Utopia, Onyxx was killed by Wither.[3]
Krakoa
Onyxx was resurrected thanks to The Five and later became a citizen of Krakoa.[4]
Attributes
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Powers
Onyxx was a mutant with a craggy granite body with the following abilities:
- Superhuman Strength
- Resistance to Physical Injury
Notes
- Onyxx's real name has only been revealed in the X-Men: 198 Files reference material.
Trivia
- Onyxx was originally planned to be killed off in New X-Men Vol 2, but writers Christopher Yost and Craig Kyle were not allowed to. As Yost bluntly put it: "I hated that character." Later, however, he was killed of in X-Force Vol 3.[5]
See Also
- 25 appearance(s) of Sidney Green (Earth-616)
- 3 appearance(s) in handbook(s) of Sidney Green (Earth-616)
- 1 minor appearance(s) of Sidney Green (Earth-616)
- 1 mention(s) of Sidney Green (Earth-616)
- 1 mention(s) in handbook(s) of Sidney Green (Earth-616)
- 16 image(s) of Sidney Green (Earth-616)