In Auckland District Court on Thursday, Judge Eddie Paul sentenced Edmonds, 18, to two years and four months' jail for the incidents in November and March. Edmonds had also admitted charges of assault, wilful damage and breaching a protection order.
"Fortunately, there were no fatalities out of this cyclone of violence," Judge Paul said.
Prosecutor James Carruthers said Edmonds committed "serious, violent offending", unprovoked and aimed at victims' heads.
Defence counsel Adam Holland said Edmonds had been "under considerable personal stress" and asked for home detention, citing his clean record while on 24-hour bail since March. Edmonds acknowledged his behaviour in March was reckless, Holland said.
"This wasn't a person who had formed a deliberate intention to harm others."
Judge Paul said the party brawl occurred after Edmonds pushed a woman against a wall, causing a fight between Edmonds and others that ended with Edmonds stabbing three people.
The woman came close to a "life-ending outcome", Judge Paul said.
In November, Edmonds attacked Derek Craig after he called police about Edmonds attacking a woman. Edmonds then punched a responding police officer twice, concussing him and breaking his nose, before punching the car window of a motorist who was "looking the wrong way, upsetting [Edmonds] in his alcohol-infused rage".
Outside court, Derek Craig told the Herald on Sunday he thought he was going to die.
The Auckland Council gardener called police after he saw Edmonds "beating the snot out of" a woman on his driveway.
Craig was punched in the head and watched as Edmonds swung a spade at him. He could not escape to his house because his terrified 12-year-old daughter was alone inside.
"My good movement and luck saved me ... I thought he was psychotic. He said 'I'm going to f****n kill you'."
Craig suffered a permanent brain injury, needed six months off work and estimated the attack had cost him $10,000. The family planned to move house because of the memories.
Despite everything, he did not regret calling police that day, Craig said. "I couldn't have done nothing. We were just collateral damage."