The "Prince of Darkness" held court from a giant leather throne, topped with a bat, at Villa Park stadium in Birmingham, firstly in a five-song solo set and then with his original bandmates for the first time in 20 years, and last time.

"It's the last song ever. Your support has enabled us to live an amazing lifestyle..thank you from the bottom of our hearts," the 76-year-old singer told the crowd after finishing the set with "Paranoid" -- the band's most famous song.

The stadium in Birmingham, central England, is a stone's throw from where the band formed 57 years ago, pioneering the hard-rock style that gave rise to heavy metal.

And the genre's big hitters were in town to pay tribute to the band that started it all.

Anthrax were one of the first acts on stage, with early arrivers giving the US rockers a rapturous welcome and getting the mosh pit into full swing.

They were later followed by a rock royalty collaboration, as Aerosmith's Steven Tyler and Rolling Stones guitarist Ronnie Wood performed Led Zeppelin's "Whole Lotta Love".

Guns N'Roses sent the 40,000 fans wild with the first chords to "Welcome to the Jungle", and there were other sets from Pantera, Tool, Slayer and Metallica.

"Without Sabbath there would be no Metallica. Thank you for giving us a purpose in life," Metallica's singer James Hetfield said.

But it was the prodigal son and his bandmates that the crowd were desperate to see, greeting them on stage with a sea of arms before moshing to "War Pigs".

"Everything was just phenomenal, you were just caught up in it. We were singing as loud as we could for Ozzy," Dave Chapman, 57, told AFP.

"He could see the support," added his 29-year-old daughter Lilly. "That's what kept making me cry..., he can see that we love him."

'Full stop' 

Many thousands around the world followed the concert online after tickets for the show sold out in just 16 minutes.

Osbourne, who revealed in 2020 that he has Parkinson's disease, joined Tony Iommi, Geezer Butler and Bill Ward for the "Back To The Beginning" show in Birmingham, where the heavy metal giants formed in 1968.

They have since sold over 75 million albums worldwide.

The stadium, which hosted Champions League football last season, was transformed into something resembling a pagan cathedral on Saturday, with fans decked in dark metal T-shirts, many sporting long hair, thick beards and large tattoos.

"Birmingham is a city which means so much to Ozzy. When it comes to heavy metal music, Black Sabbath forming and his love of Aston Villa -– it all started here," said his wife, Sharon.

All profits from the show will go to charities including Cure Parkinson's and Birmingham Children's Hospital.

Osbourne's diagnosis led to him pausing touring. But Sharon told the BBC the Villa Park gig would be his last. "This is his full stop," she was quoted as saying.

Rich Newlove, 34, called it a "bittersweet" experience "because it's his last show".

"It's a good send-off... he seems fitter and healthier than I thought he would be."

'Greatest' 

The Smashing Pumpkins frontman Billy Corgan was one of the early performers, saying before the gig that "this might be the greatest one-day lineup in the history of rock 'n' roll".

The show is expected to deliver the area a multi-million-pound boost, with hotel occupancy in Birmingham city centre expected to have reached close to 90 percent.

Osbourne's live performances at the height of his hedonism have gone down in rock folklore, particularly a 1982 gig in Des Moines, Iowa, when he bit the head off a bat on stage.

Osbourne says he thought a fan had thrown a fake rubber bat onstage, and it wasn't until he took a bite that he realised it was real.

"I can assure you the rabies shots I went through afterwards aren't fun," he told US TV host David Letterman in 1982.

But there was no repeat performance on Saturday.

Eager to soak in the historic occasion, many came without tickets, including Derya, who travelled from Cologne with her partner.

"We are here, hearing the concert even if we cannot see the bands," she told AFP.