A judge was told the alleged event involves prisoners smoking the dangerous drug – that can induce a zombie-like state in users – before trying to run round a circuit of the jail's landings as quickly as possible.
However it is said nobody has been able to complete the course before collapsing or blacking out.
Details of the alleged event were revealed to Wolverhampton Crown Court by Mr Richard Davenport, defending Joshua New who had been held in custody on remand for six months.
The character of the 24-year-old defendant had been drastically altered after he was encouraged by friends to start taking cocaine at the age of 21 and became addicted, it was said.
This transformed him from being calm and pleasant into a paranoid, violent individual obsessed with an unfounded belief that his partner was being unfaithful, the court heard.
He systematically bullied his victim for two months leaving her in constant fear of violence, said Mr David Bright, prosecuting.
The threats came to a head on July 20 when he completely lost control and held her captive for more than six hours.
The prosecutor explained: "He was motivated by jealousy, lost control, grabbed her hair, headbutted her, banged her head on the wall, hit her with a lamp and grabbed her by the throat whilst holding a fist in front of her face."
New also assaulted her and her close friend on another occasion. Mr Davenport said: "He accepts responsibility for everything he did. His character was transformed after he started taking cocaine and developed this obsessive behaviour.
"He has been held on remand in custody for six months. This was a devastating experience for him but has made him sit up and think about his life. He says he has been sharing cells with inmates who take Black Mamba.
"He has also told me that the prisoners hold Mamba Olympics in which one of them, watched by the others, smokes a wrap of the drug before trying to run round the landing.
"Apparently nobody has managed to complete this without collapsing and losing consciousness for some time.
"This has shown the defendant the way he is heading if he carries on with drugs and hopefully has helped to change his ways."
New, from Dudley Street, Sedgley, admitted assault, false imprisonment, harassment and criminal damage and was given a two-year prison sentence suspended for 18 months.
He was ordered to complete a rehabilitation course and pay £500 compensation to his victim whom he is banned from contacting by a restraining order.
Judge Michael Challinor told him: "The six months in custody has been your punishment. It must have been like a nightmare. Now I want you to get a job, settle down and stay off the drugs and the drink."
Black Mamba is an artificial cannabinoid drug which can cause very serious side effects including mental health problems, psychosis and sometimes a deep zombie-like state.
Birmingham Prison is a Category B jail in Winson Green that was operated by G4S from 2011 until being returned to HM Prison and Probation Service in August 2018.
The Ministry of Justice said: "We do not recognise this claim as being true."