An aspiring rapper committed a "horrendous" murder by bashing a sleeping man with a metal bar and leaving him to die over the course of 45 minutes, a court has heard.
Coskun Jaques Marius, 30, pleaded guilty on Tuesday in Brisbane Supreme Court to the manslaughter of Tane Tahi Manawa, 38, at the victim's Surfers Paradise home on May 10, 2019.
Marius pleaded not guilty to the murder of Mr Manawa on the grounds of having an abnormality of the mind at the time.
Crown prosecutor Michael Lehane did not accept the guilty plea as grounds to discharge the indictment for murder and the case proceeded to trial.
Mr Lehane told the jury Marius attacked Mr Manawa, also known as Dre, with the intent to kill over a "list of gripes" that culminated with him boasting about a large Chinese meal.
"(Marius) had not eaten in the past few days and had to settle for a little bowl of stir fry that he had to eat cold," Mr Lehane said.
He said Marius had been unemployed for months and had been doing favours for people in return for places to sleep.
Marius had claimed Dre, a methamphetamine drug dealer, had "treated him like a dog" and constantly demanded he clean the house, before evicting him.
Soon after, Marius returned to the house to drink alcohol with female friends while Dre was dining at a restaurant.
Mr Lehane said Marius told police he was starving, in withdrawal from meth and tipsy on cask wine before he "exploded" and grabbed a lateral pull down bar from the garage when he heard Dre bragging about his meal.
The jury was shown images of a bloodstained reclining armchair where Dre was sleeping before the attack.
"(Marius) committed a horrendous act out of anger, resentment and pure spite, smashing Dre's face and skull, bringing the bar down many times," Mr Lehane said.
He said a forensic pathologist found Dre lived for 45 minutes after the attack.
NSW police arrested Marius two days later after he left the house in Dre's white van and drove to Coffs Harbour.
While being driven back to Queensland, Marius told police an alter ego who had lived in his head since childhood and took over during times of anger could have killed Dre.
Marius's barrister Lars Falcongreen said his client had admitted to unlawfully killing Dre but the "heart of the case" was his diminished capacity.
"He was in a state of abnormality of mind that impaired one or more of (his) capacities to understand what he was doing, control his actions or know he should not do the act," Mr Falcongreen said.
He told the jury to pay particular attention to any evidence concerning whether it was more probable than not that Marius's capacities were significantly affected, including his statements about having an alter ego.
The trial was due to run for another nine days before Justice Glen Martin.