Looks like it's pistols at dawn between MOL and Jim McAuslan...
The Guardian Mr O'Leary revealed that Buzz was likely to lose €30m (£20m) this year. He claimed his strategy would transform its fortunes within 12 months to produce a profit of €10m.
In a message that appalled unions, he said there was no question of negotiating: "There's no point in sugaring pills. This is losing shedloads of money and has to be turned round. We're not going to sit around having consultations or going through some laborious process. This is not stopping for anybody. For those who don't want to sign up to the project, the door's out there on the left."
At least 100 of Buzz's 500 staff will lose their jobs. The brand will disappear, to be swallowed up by Ryanair. Among the first routes to go will be Amsterdam, Paris and Frankfurt - all to "high cost" airports where planes take longer to turn around.
Mr O'Leary said Buzz's problems were attributable to its Dutch owner, KLM: "It got saddled by KLM with the !!!!tiest set of aircraft in the fleet, flying to !!!!ty airports and with a few too many employees for an airline carrying 2m passengers."
He said he was sure his plans would provoke "hell, brimfire and damnation" but insisted that if unions attempted to strike, he would "close down" the airline.
The British Airline Pilots' Association reacted with dismay. General secretary Jim McAuslan said he had asked for a meeting with Mr O'Leary. "However charismatic he may be, he is not above the law. You cannot go just hiring and firing people. And you don't motivate people by putting the fear of God into them."
The TGWU also expressed concern, emphasising its "strong determination to stand up for our members' rights in the face of robust warnings on job losses".
Ryanair disclosed its plans for Buzz alongside nine-month results showing that its own low-cost strategy continued to be a moneyspinner, with pre-tax profits up 60% to £216m.
But Buzz's demise caused particular gloom in Bournemouth, earmarked as its second base. Buzz had already sold 55,000 tickets for six destinations from the south coast town, which were due to begin on March 30.
Bournemouth airport's managing director, Glyn Jones, said he was "surprised" by Ryanair's decision, pointing out that the airport had built an extension to handle Buzz's flights. Christopher Chope, the local Conservative MP, said the airport's plans would be ruined.