Stabber 'lost control' after rapper broke into his home

A man "lost control" before fatally stabbing rapper Mak Muon, having had a gun held to his head and two Gucci bags, an iPhone, cash and cash stolen from his home, a jury has heard.

Mr Muon had broken into a western Sydney granny flat just hours before his body was found near an Emu Plains reserve about 8am on September 24, 2020.

The 22-year-old and his two associates were armed with a handgun and knives when they entered the property, seeking the resident's cash and motorbikes.

The armed resident then pursued the rapper with the aid of three friends and was later charged with murdering Mr Muon.

The three co-accused joined him in the NSW Supreme Court on Tuesday, where they stood before Justice Dina Yehiya, each denying charges over Mr Muon's death.

Although the resident did not deny stabbing the rapper, causing his death, he pleaded not guilty to murder and pleaded guilty to the lesser charge of manslaughter.

Barrister Tony Evers told the jury his client had not intended to kill anyone but acted in the heat of his emotions.

He was armed with a knife when he confronted the man because he was in front of people who had attacked him "just hours before," Mr Evers said.

"He simply lost control of his emotions (when he saw Mr Muon), given what had happened to him," he told the jury.

Mr Muon was joined by two other men when he had held the man at gunpoint in his home, yelling at him to give them cash.

Mr Muon had pointed the gun not only towards the resident, Mr Evers said, but also at his mother who had "bravely" confronted the men as they walked her son out of the granny flat.

The man's girlfriend, woken up by a loud bang, was held down on a bed by one of Mr Muon's armed associates in a bid to retrieve her phone after she'd called for help.

She later could identify the bang had been the security door of the granny flat falling to the ground.

Other residents in the main house on the property came outside after a phone call from the girlfriend warning of intruders.

The woman held back tears as she recounted seeing Mr Muon hold a gun to her partner's head.

"I was whispering, I was scared," she told the jury.

"I said 'you need to come down - someone's breaking in''."

Moments after Mr Muon and his partners fled the home, the resident had called three friends to assist in retrieving the stolen bags, iPhone and cash, the court heard.

The girlfriend then tracked her stolen phone through a locator app on her partner's phone, allowing the man and his helpers to track Mr Muon.

A crown prosecutor said the four accused were armed with a screwdriver and knives.

The four men had caught Mr Muon after an associate crashed their car into a creek and they ran in opposite directions.

Mr Muon was stabbed in the chest with a knife, the blade remaining in his chest as the handle fell off.

One of his associates went back to the car, finding Mr Muon's body on the ground nearby before calling emergency services.

The trial continues.