He grilled the Māori MPs, calling them "ineffective representatives" and said Māori were more than capable of getting to parliament without special seats.
Seymour also used his speech to attack the Government, singling out Jacinda Ardern as a "show Prime Minister", criticising Finance Minister Grant Robertson as "weak" and calling Labour's deputy leader Kelvin Davis "totally incompetent" and an "embarrassment".
He called Arden out for not being able to scare anyone and not understanding anything about the economy.
"The economy could go straight over the cliff and Jacinda will go on smiling as it all crashes around her," Seymour told party faithful at ACT's annual conference in Auckland this afternoon.
And he didn't stop there, Seymour called Forestry Minister Shane Jones out for attacking business and pouring millions of dollars not just into Northland but his own neighbourhood - "calling it pork barrel would be unfair to pigs."
"The growth in Government over the past two decades has not delivered better outcomes for New Zealand. We need smaller, smarter government.
"New Zealand has too many politicians for its size. Our Government costs more and delivers less than it did 20 years ago."
Reducing the size of New Zealand's Parliament is not a new idea - a referendum at the 1999 general election calling to downsize to 99 MPs won 81.5 per cent support of voters. MPs ignored the result.
Seymour also wants to cap the size of the executive at 20, noting that the current Government was "far too big" and had 31 people in roles.
"Almost half of the Government MPs hold a position in the Executive. We have too many pointless ministerial portfolios. They are not improving the lives of New Zealanders and this bill will do away with them."
"Our plan would also require all parliamentary candidates to stand in an electorate, and all elected list MPs would be required to open an office in the electorate in which they stood."
On the topic of changing the party's name, Seymour said "reform" and "liberal' were being considered.
"I think people like the liberal name. There is some question around what it means and one thing about a party name is that it has to be very clear.
"Some people have criticised ACT in that regard while other people say well at least you've got a name that is well known."
In last year's election ACT received just 13,075 party votes, 0.5 per cent of the vote. Seymour returned to Parliament alone, after winning his Epsom seat.
Since then Seymour's foray in Dancing with the Stars has made him a household name and there is no question of him not contesting Epsom again.
Formed in 1994, under the leadership of Richard Prebble, the party had nine MPs after each of the 1999 and 2002 elections.
For the past three elections, it has had only one MP, by dint of winning the Epsom seat in an electoral accommodation with National.
Seymour has been focused on the euthanasia bill he is sponsoring, the End of Life Choice Bill.
He acknowledged there were opportunity costs working on the bill but it was by no means all he did.
He had led a protest march up Queen St with students affected by the decision to close charter schools and for the past week, he had spent a lot of time on the free speech issue.
Asked to sum up the state of the party, he said: "I think Elton John summed it up well. He said 'I'm still standing'."