A thug claimed he targeted a gangland figure in a prison 'napalm' attack because he was bullied.
Matthew Grady was jailed last week after pouring the contents of a kettle over John Hardie at Shotts prison, where he is serving time for trying to murder his ex-girlfriend.
Other prisoners dragged the 35-year-old away as he threw punches at Hardie, who was jailed for 20 years for his role in a plot to murder crime kingpin Steven 'Bonzo' Daniel.
Hardie was uninjured in the attack, but Grady suffered a black eye after being dragged away.
Staff later discovered sugar in the kettle had not melted.
Grady was jailed in 2017 after attempting to murder Siobhan Stevenson. The brute slashed her face amid claims he had cheated on her.
He appeared via video link from HMP Glenochil at Hamilton Sheriff Court and admitted the assault of May last year. He was given an additional 15 months by Sheriff John Speir and told it will begin after his current 10-year sentence ends.
Depute fiscal Jennifer McCabe said: "The complainer was in a communal area of the prison and the accused was observed on CCTV exiting his cell with a kettle in his hand.
"He quickly walked towards the complainer and as he got closer, he threw the contents over him and then threw punches at him.
"This was observed by a prison officer who pressed the alarm for other officers to attend while the complainer was helped by other prisoners to try and stop the accused assaulting him further.
"Prison officers took hold of the accused and escorted him to his cell.
"Officers observed the kettle lying on the floor and the floor sticky.
"The sugar in the kettle did not dissolve and it was still all over the kettle in granular form.
"Neither man required medical treatment."
Elaine Rae, defending, said: "The complainer had threatened him on numerous occasions and Mr Grady knew that by assaulting him, that would cause this to stop.
"He was the only person who suffered any sort of injury.
"He has been moved to HMP Glenochil and is keeping his head down."
Sheriff Speir said: "I take into account the difficulties that you found yourself in but I know this sort of behaviour cannot be excused because the consequences could have been very significant indeed for Mr Hardie."
Attacks with sugar in boiling water are commonly known as 'napalm' in prison circles because the mixture sticks to the skin and intensifies burns - similar to napalm bombs.
Hardie was caged for 20 years for a plot which saw a gang of six men carry out a string of savage attacks across Glasgow.
Bonzo was chased in a 100mph car chase before his motor was rammed and he was viciously attacked with a machete leaving him scarred for life.
In May 2019, Hardie along with Brian Ferguson, Andrew Gallacher, Robert Pickett, Andrew Sinclair and Peter Bain were jailed for a total of 104 years at the High Court in Glasgow.
Last year he admitted having two illicit mobile phones in his cell at HMP Shotts and was caught trying to flush one down the toilet.
