The prisoner, who has attacked over two dozen guards while in jail, has even had management figures at the prison take it upon themselves to go out and buy him games for his Playstation.
There was uproar when another prisoner was given a cake on his birthday just days after a knife attack in Mountjoy which left two officers badly injured.
Speaking yesterday, Prison Officers' Association assistant secretary general Gabriel Keavaney said that another prisoner, Leon Wright, has had an aquarium installed to pacify him.
"He has been given a Playstation, the management have gone out and purchased games for him. A fishtank has been put out on the landing to pacify him.
"This guy has very seriously assaulted staff in the past.
"They are now talking about building a garden for him off the landing for him to have some time in, this is completely unacceptable. He has a huge amount of complaints and a huge track record of assaulting staff."
Wright has over 220 complaints against him since being incarcerated for two violent attacks in Dublin city.
The 27-year-old stabbed two people in completely random attacks on Grafton Street in 2013. He was out on bail when the attacks occurred.
Keavamey says several prison guards in riot gear are utilised every time they need to enter his cell.
"There seems to be no loss of money when it comes to dealing with these people, I mean we’re in riot gear at the moment dealing with this guy, he’s that dangerous."
He revealed the prisoner also enjoys other privileges.
"They also bring in special brown bread for him which no other prisoner has access to. Every time he opens the fish tank there has to be three officers in riot gear, he’s that dangerous."
Wright is kept in a special separation unit in Portlaoise Prison as he is considered too dangerous and violent to be kept on a normal wing.