That is Angus Taylor's warning to Australians as long-standing Liberal supporters flock to Pauline Hanson's party.
One Nation did not have solutions for working people, the opposition leader argued in a major speech on Thursday night.
"One Nation claims to offer a way out of our national malaise," Mr Taylor told the Sydney Institute.
"In reality, they would only make things worse."
The Liberal leader described One Nation as "a column of smoke".
"Long on rhetoric but short on substance, One Nation's offering is a random grab bag of poorly defined, contradictory and constantly changing positions that leave no clear sense of who they are or what they stand for," he said.
"Their longest-serving MP thinks the United States is the 'world's greatest terrorist organisation' and their newest MP is already voting with the Greens and teals."
Support for the coalition has crashed to record lows in recent opinion polls and it now trails One Nation.
Mr Taylor said Australia needed a team to address the challenges that lay ahead.
"It is beyond any one person," he said.
"Look at One Nation's team. In the end, it is a one-person show."
Just four of One Nation's financial commitments could cost the federal budget a trillion dollars over a decade, the opposition leader said.
"They have no clear or credible plan for how they'd pay for these commitments," he said.
Mr Taylor is aiming to return to the coalition's traditional stronghold of the economy in a bid to gain ground.
"Under Labor, government has gotten bigger and Australians have gotten poorer. That is the brutal truth," he said before the speech.
"More spending, more bureaucracy and more public sector workers have not delivered better services or higher living standards."
Mr Taylor said the opposition would reduce government spending, end mass migration by capping it below the number of homes being built and deliver automatic tax cuts each year through its plan to index tax rates to inflation.
"The coalition has a plan for a fairer, freer and better Australia where we will restore Australians' standard of living and protect our way of life," he said.
Support for One Nation has surged, at one point surpassing Labor on primary votes.
But Senator Hanson's party has recorded a dip in its backing following her first address to the National Press Club in June, when she called for Australia to become a monoculture.