The former flatmate of a man on trial for stabbing his ex-wife to death says the accused was "fixated" on killing the woman.
Li Manchao is on trial in the High Court at Auckland after pleading not guilty to murder and breaching a protection order.
The 65-year-old is accused of attacking his ex-wife Yang Zhimin on Westgate Drive, Massey, about 8.30am on 29 July, 2019.
It's the Crown's case Li planned and prepared to kill Yang after the High Court ruled against her in a martial property dispute.
Today, Garrick Protheroe, who lived with Li in Henderson in 2018, told the court the defendant was obsessed with taking revenge on his ex-wife.
"From almost day one he was fixated with the fact his wife had done him the dirty and he was somehow one day going to get even with her."
He said Li referred to his ex-wife as "the bitch" and told him not to be stupid when he said his life would be better if Yang was not on the planet.
"I said that's ridiculous; no woman or no person is worth that sort of action because at the end of the day you're going to end up in jail. And who's going to be worse off?"
He said Li seemed to take his advice on board but then reverted back to planning; showing Protheroe a box of weapons including a number of rifles, a hunting knife and a large meat cleaver.
"That was the intereting thing with the meat cleaver because he said to me 'do you think this would be enough to kill somebody?' and I said 'it'd do a pretty good job'."
"And so he went out in the backyard and had a go at a tree and chopped a couple of branches off and said 'oh well that seems to work alright'."
Protheroe said he got the impression Li changed his focus from killing his ex-wife to injuring her in such a way she would not forget the pain she had caused him.
He said he grew so uncomfortable with Li's comments and actions he eventually went to police with his concerns.
The jury has now heard Li had breached numerous protection orders against him over the years.
Yang Zhimin told police Li had appeared at her workplace and in a supermarket car park and stood in front of her and just stared.
In a statement she made when applying for her final protection order, read aloud in court by Constable Sara Brooksmith, Yang said she was scared.
"I don't know how crazy Manchao Li could go. I'm scared of going grocery shopping, scared of answering phone calls when I don't know the caller number, scared of anyone knocking on my door.
"I live on my own. I can only rely on the court and police for protection."
Constable Renee Beveridge served Li his final protection order in April 2019, two months before Yang was fatally attacked, and said his reaction was strange.
"I struck me a little odd that he seemed to be almost in disagreement for why he would be receiving a protection order."
Today, the jury also heard Li launched an anti-crime petition - after numerous burglaries at the home he and Yang shared when they were together.
The petition - calling for harsher penalties - was accepted by former MP and deputy Act leader Kenneth Wang.
The trial before Justice Jagose and a jury of seven women and five men is set down for three weeks.