Former Florida Gov. Jeb Bush, Sen. Marco Rubio’s mentor, is warning the political world to steer clear of a “risky” Rubio.

It’s the latest in a series of escalations in the open war between Rubio and Bush, a war that broke out in public on the debate stage in Boulder, Colorado, earlier this week–a round in the fight that Rubio clearly won. Now, Bush’s team is striking back harder.

“Marco Is A Risky Bet,” reads the header on slide 19 of a third quarter campaign briefing presentation posted online this week.

Among other things, the slide walks through Rubio’s record—or Bush’s argument that Rubio lacks a record of accomplishment—and scandals in which Rubio has been involved. But most important is an implication that the team vetting vice presidential candidates for 2012 GOP presidential nominee Mitt Romney found something on Rubio that quickly disqualified the senator from getting the nod to be Romney’s veep.

“Those who have looked into the Marco’s background in the past have been concerned with what they found,” the last bullet point on slide 19 reads.

While not directly a reference to the Romney vet, that bullet point is certainly implying that dirt someone found on Rubio is why Romney didn’t select Rubio—then a strong favorite as a vice presidential possibility—as his running mate. A Bush campaign aide anonymously told U.S. News and World Report that’s exactly what that line was referencing.

So the story goes, Romney’s researchers found something so horrific about Rubio that the governor couldn’t select him as his running mate in 2012. It’s always been unclear what that might be that they found, and the files are not available publicly at this time. Beth Myers, a top Romney confidante who oversaw the vetting process, told Politico that’s not accurate.

“As the senior Romney advisor who handled VP vetting and had access to all the vetting documents, I can say that Senator Rubio ‘passed’ our vetting and we found nothing that disqualified him from serving as VP,” Myers, who is actually a Bush supporter not a Rubio backer, told Politico. “The Bush aide referred to in this article is simply wrong.”

Even so, many political insiders and former Romney campaign staffers over the past several months—including those with direct knowledge of the vetting process he had for VP picks—tell Breitbart News that there is something to this despite Myers’ claims. As such, with the rumor mill in full swing—few in Washington believe Myers’ denial—the only way Rubio could put an end to this is if the full file, with all accompanying Romney campaign vetting documents, became public.

The rest of the stuff on slide number 19 from the Bush campaign’s presentation details things—mostly publicly known—about Rubio that Bush’s team thinks would cause donors serious caution.

“No accomplishments, negating hit against Hillary Clinton,” the first bullet about Rubio reads, which leads right into the second: “Marco’s ‘tomorrow versus yesterday’ argument will be widely ridiculed by the media while running against ‘first woman president.’”

From there, the slide goes into the Rubio scandals.

“Misuse of state party credit cards, taxpayer funds and ties to scandal-tarred former Congressman David Rivera takes away line of attack on Hillary Clinton,” bullet point three reads, before bullet point four questions Rubio’s connections with a major billionaire donor: “Closeness with Norman Braman, who doubles as a personal benefactor raises major ethical questions.”

Then it goes after Rubio’s lack of serious experience in management. “Outside of lobbying and legal consulting, no credible experience beyond government,” bullet point five reads, before bullet point six sticks the knife in: “Never been in charge of anything larger than two dozen people.”

Slide 20, a follow-up, goes even further by arguing in its headline that “Those closest to Marco choose Jeb.”

“Rubio has only one endorser from Florida’s Congressional delegation, Governor Bush has 11,” the first bullet point on slide 20 reads, before the second says: “Governor Bush has received the backing of eight former Speakers of the Florida House.”

“Top Congressional Hispanic Floridians Mario Diaz-Balart, Carlos Curbelo and Ileana Ros-Lehtinen have endorsed Governor Bush,” the third bullet point reads before the fourth says: “Twenty of 26 GOP senators in Tallahassee have endorsed Governor Bush, only two have endorsed Marco.”

“Marco’s former Senate campaign manager and others close to him have also joined Governor Bush’s team,” the fifth bullet point reads, before the sixth takes it even further: “Marco hasn’t received a single endorsement from a fellow U.S. Senator. Governor Bush has been endorsed by three, as well as 20 House members.”

The next page, slide 21, calls Rubio a “GOP Obama.” Headlined “Experience Matters,” Bush’s team unloads more on Rubio there. “We need to offer a contrast to the current president,” Bush’s team writes. “Hillary will pitch competence and experience. Marco is a GOP Obama.”

“Rubio and President Obama have strikingly similar profiles: first-term senators, lawyers, and university lecturers, served in part-time state legislatures for eight years, had few legislative accomplishments, and haven’t shown much interest in the process of advancing legislation and getting results,” the second bullet point on that slide reads.