Jeremy Corbyn has accused Conservatives of risking a "war between generations" with a manifesto that pitches young against old.
Addressing activists at a rally in Birmingham, the Labour leader called on Theresa May to ditch an "anti-pensioner package" which inflicted a "triple whammy of misery" on older voters by cutting protections for the state pension, means-testing winter fuel allowance and forcing them to pay for home care.
But he insisted that a better deal for pensioners must not come at the expense of the "left-behind generation" of younger people, but should be funded through higher taxes on top earners and big business.
"There is no trade-off between young and old - and there should be no trade-off," Mr Corbyn said.
"Society should not be setting the future of our young against security for the old. We have the wealth to offer a decent, secure life for all."
Setting out Labour plans to abolish university tuition fees and build homes for young people, Mr Corbyn said his vision was "not a war between generations, it's a unity between generations to create a better society for all".
He said: "Labour's proposals will ask the top 5% of earners and the big corporations to pay a bit more, to help address these problems.
"That way we can make sure that young people can get homes and pensioners can heat their houses in winter.
"That way students can leave college without a huge burden of debt and older people can have their income protected through the "triple lock", which only Labour will guarantee."
Mr Corbyn was cheered as he told supporters that "we are moving on to win this election", and claimed that the Conservative campaign was "unravelling" as voters examined their policies.
"Get on any bus, get on any train, go in any cafe, talk to people," he said. "The whole discussion and the whole debate is unravelling from the Tory point of view, because people are saying `Hang on, why are so many young people in such stress? Why are so many older people being threatened by this Government? Can't we as a society, as a country, as a people do things differently and better?
"I tell you what - we will."
Mr Corbyn urged young people to ensure that they are registered to vote by the deadline of midnight on Monday, so they can cast a ballot in the June 8 general election.
And his call was echoed by EastEnders actress Maddy Hill, who welcomed him onstage as "our next prime minister" with an appeal to young people: "Don't stay silent, register to vote by midnight on Monday and then use that vote on June 8. Get out and vote for a Labour government under Jeremy Corbyn, a Government that will stand up for you and all of us."
There was a raucous atmosphere in Birmingham's International Convention Centre, where Mr Corbyn was welcomed by loud chants of "Jezza, Jezza".
One supporter shouted "get them out" and "evil scum" when the Tories were mentioned. But most of the 2,000 or so present focused their efforts on showing their support for the speakers.
There were loud cheers when shadow chancellor John McDonnell pointed out that Labour's manifesto is fully costed, unlike the Conservative document which was published without costings.
Shadow chancellor John McDonnell said the Tories were "loading up young people with debt" through tuition fees and doing "nothing" about skills and training.
"Why? Because they think they don't have to bother about young people because young people to them don't matter because they don't vote," he said.
"Well I tell you, young people matter to us - we believe education is a gift from one generation to another."
Mr McDonnell said voters had the "opportunity of a lifetime" and insisted there was "all to play for" ahead of June 8, despite the Tories narrowing but still double-digit lead over Labour in many polls.
"Let's get out there and win this election, let's carpe diem (seize the day), let's seize this opportunity, with courage and determination, we can win this election despite what they throw at us."
A Conservative spokesman said: "The biggest threat to every generation in this country is getting Brexit wrong. Get Brexit wrong and we get everything wrong - from looking after our elderly to paying for our children's education.
"Our nation's economic security and our standing in the world depends on getting the Brexit negotiations right.
"If anyone is thinking about lodging a protest vote because of Jeremy Corbyn's scare campaign, here's the thing that's genuinely terrifying: if Theresa May loses just six seats then we will have a hung Parliament with Jeremy Corbyn as our prime minister, in charge of Brexit and propped up by the Lib Dems and SNP."