Even before all the candidates took the stage in Detroit on Wednesday for the second night of the latest Democratic primary debate, the looming conflict at center stage was already apparent.
Booker sharply criticized Biden over criminal justice reform, Inslee hit Biden over his plan to combat climate change, while former Housing and Urban Development Secretary Julián Castro said Biden hadn't "learned the lessons of the past" on immigration.
Here are five takeaways from the night two of the second Democratic primary debate, the final contest before the Democratic National Committee imposes stricter qualifying standards, making it tougher for a large swath of candidates to make the stage.
Biden, Harris feel the heat, continue their beef
For those looking for a cooling off in the debate between Biden and Harris, Wednesday night was a disappointment.
The two candidates, who are towards the top of the pack in polling, criticized each other's health care plans at length and continued to take aim at each other's records.
"You can't beat President Trump with double talk on this plan," said Biden, who criticized Harris for offering a plan that would eventually eliminate private insurance as an option for Americans seeking healthcare insurance.
"Unfortunately Vice President Biden you're just simply inaccurate in what you’re describing," Harris said following Biden's critique of her plan, "The reality is that our plan will bring health care to all Americans under a Medicare for All system."
But even as the two continued to spar, they took incoming fire from almost every candidate on stage Wednesday night,
Challengers come for the front-runners
Nearly every candidate took advantage of the fact that they were on the same stage as Biden and Harris, lobbing constant attacks and attempting to dissect their records.
New York Sen. Kirsten Gillibrand took aim at Biden over women's rights, Gabbard said she's "deeply concerned" over Harris' record on criminal justice, while Washington Gov. Jay Inslee implored Biden to approach the issue of climate change with more urgency.
At times, multiple candidates ganged up on Biden, who continually defended his record.
"I don't know what happened except you're running for president," Biden said at one point to Gillibrand when she challenged him over previous comments he made about women working outside the home.
Castro also went after Biden on the issue of immigration and defended his position on decriminalizing crossings at the U.S.-Mexico border.
"Mr. Vice President it looks like one of us has learned the lessons of the past and one of us hasn't," Castro said.
Don't expect the attacks on Biden to dissipate as candidates feel the increased pressure to build support heading into the critical months ahead of the Iowa caucuses.
Booker gets his moment
Booker, who continues to lag behind most of the pack in the polls, continually implored the stage not to play into President Trump's hands by attacking each other, while at the same time sharply critiquing Biden's record.
"Mr. Vice President, there's a saying in my community that you're dipping into the kool-aid and you don't even know the flavor," Booker said after Biden pointed to his record managing the police department as the Mayor of Newark.
Even amid his cogent attacks on Biden, Booker was able to offer a firm reminder to the party of their ultimate goal: defeating Donald Trump.
"I just want to say again we are playing into Republican hands who have a very different view and are trying to divide us against each other," Booker said.
Impeachment remains a question mark
Unlike night one, the candidates were directly asked about the issue of impeachment, and although there was agreement that President Trump should be held accountable, the way forward remains unclear.
"While with a move for impeachment, we have to remember at the same time the American people are out there looking for us to do something for them in their lives," de Blasio warned.
"I really do believe we can walk and chew gum at the same time," Castro argued, saying that Democrats can still pursue impeachment while articulating a clear vision for the country.
Neither Harris nor Biden offered an answer on the subject, perhaps allowing them to avoid one of the more perilous political issues of the day.
Bennet, Inslee make their push as Yang takes advantage of his airtime
Bennet and Inslee, two candidates at risk of missing the fall debate stage, both had standout moments Wednesday night, with both urging action on two issues at the core of their campaigns: education and climate change.
"Let's fix our school system and maybe we can fix the prison pipeline that we have!" Bennet, the former Superintendent of Denver Public Schools, said in one of the night's more impassioned moments.
Inslee, who has centered his campaign entirely around the issue of combatting climate change, was able to push the issue to the forefront Wednesday night, and his criticism of Biden allowed him to again distinguish himself as the leader of the pack on an issue of growing importance to Democratic voters.
"We cannot work it out. We cannot work this out. The time is up. Our house is on fire," Inslee said, pleading with Biden to heed his warnings on the issue.
Another candidate who did not have a major impact during the first debate that was able to get a clearer message across was entrepreneur Andrew Yang, who pushed his trademark policy of universal basic income and was more precise in his argument for why he can beat Donald Trump.
"We're up here with makeup on our faces and rehearsed attack lines, playing roles in the reality TV show. It's one reason why we elected a reality TV star as president. We need to be laser-focused on solving the real challenges of today," Yang said in his well-received closing statement.