As the Social Democrats (SPD) head for the opposition benches, an unlikely match-up between the FDP, Chancellor Angela Merkel's conservative CDU/CSU alliance and the Greens appears to be the only option for government.
The prospect of a "Jamaica" alliance, named after the parties' colours of black (CDU), yellow (FDP) and green has thrown the gulfs between the parties' political convictions into stark relief.
Bringing the three together on climate, economic and fiscal policy would be difficult enough, but the FDP's biggest spanner in the works could come on Europe.
Its youthful party leader Christian Lindner has rejected any reform of the euro single currency area -- pushed by French President Emmanuel Macron and cautiously welcomed by Merkel -- that would create a centralised budget to smooth out national economic crises, managed by a eurozone finance minister.
And the FDP would prefer to use Germany's bumper budget surpluses to offer voters and businesses €30 billion in tax cuts, rather than investing the cash at home and shrinking the country's trade surplus as its foreign partners have demanded.
"Of course we're ready to take on responsibility," Lindner told journalists in Berlin Monday, while warning "there would be nothing worse than continuing the policies of the past four years with new colours".
Greener than thou
"We think it's necessary for the law to encourage individual responsibility" in European countries' finances, Lindner declared.
The FDP would be prepared to back some increased investments using existing mechanisms like the European Investment Bank, he said.
But "we couldn't agree to a eurozone budget which would automatically lead to fiscal transfers in the EU, that wouldn't solve problems but make them worse," Lindner added.
The press conference saw the 39-year-old swipe at both prospective coalition partners, claiming that CDU, the SPD and the Greens were indistinguishable in the previous parliament.
He took on the Greens on their home turf, accusing them of being obsessed with banning fossil fuel power plants and cars rather than more easily reached "low-hanging fruit" of carbon dioxide emissions reduction.
"The Greens will have to tread a very long road to reach discussions about Jamaica," Lindner insisted.
One Ukrainian journalist pinned the party leader down with a question on the annexation of Crimea by Russia.
Lindner had argued during the campaign that the issue should be "compartmentalised" in favour of normalising economic relations with Russia by gradually dismantling EU sanctions against Moscow.
"The annexation of Crimea (by Russia) is a breach of international law," he said.
"There would be no question for the FDP of lifting sanctions without getting something in return."
Imagination has its limits
Lindner also took a moment during the press conference to slam the SPD's immediate ruling out of returning to government.
The Free Democrats' caution about entering government dates back to 2013, when the party failed to clear the 5.0-percent hurdle to make it into parliament - after four years of coalition with Merkel when they struggled to make an impact.
The party is back with 10.7 percent of the vote, enough for 80 seats - but "Lindner knows how quickly he could lose his 10 percent" if he makes too many concessions, news weekly Der Spiegel commented.
Nevertheless, there are common points with the Greens that could feed into a joint programme for modernising the German economy.
Both parties insist on reform for the uneven state-by-state patchwork of the education system, focus on speeding up Germany's creeping progress in building high-speed internet connections and place a high value on civil rights.
"Governing won't be easier for the (conservative) Union in the coming years. But it could be a better government for the country," commented conservative newspaper Frankfurter Allgemeine Zeitung.
Asked about how coalition talks might go, FDP deputy leader Wolfgang Kubicki told reporters "my imagination is unbounded, but it has its limits."