Mr Luxon's National party swept Labour and Mr Hipkins from office at the October election, the pair clashing on the campaign trail and in a string of debates.
However, he saved his most venomous lines for the his first speech in parliament as prime minister, calling Mr Hipkins "bitter and twisted" and lucky to have a job.
"They started this last term with everything that they needed to actually set up a political dynasty for a decade and they squandered it," he said.
"Labour is sitting over there wondering who to blame for them going from 65 MPs ... to the 32 uncomfortable people over there with survivors' guilt."
"How has he survived when nearly half of his caucus lost their jobs under his leadership?
"He is like an arsonist who, having thrown an accelerant all over the joint and lit the place up, he doesn't just slink off ... he just simply loiters and hangs around at the scene of the crime.
"You have to ask the question, 'Why is he here?'."
Mr Hipkins gave as good as he got during his speech in the term-starting address-in-reply debate, saying Mr Luxon had presided over possibly the "most shambolic beginning of any government in New Zealand's history".
However, Mr Hipkins' attacks were in keeping with usual behaviour of an opposition leader, whereas Mr Luxon's eagerness to engage in political tit-for-tat as prime minister caught the eye.
Mr Luxon, a former Air New Zealand chief executive, appears set to walk a different path to the last election winner, Labour's Jacinda Ardern.
Ms Ardern became internationally famous for her politics of kindness, leaving attack-dog style parliamentary efforts to her deputies and ministers.
The National party leader's fury shows the return of business-as-usual sparring from the dispatch box.
His attack was one part of a 30 minute speech, which outlined his government's agenda and included hearty thanks to his caucus.
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