For some time now, rumours have been flying about Ozzy Osbourne’s public appearance schedule, with one in particular centring on a young Greek muso.

The whispers were confirmed on August 22 when 28-year-old Gus G officially performed live with the heavy metal veteran.

Guitarist Gus G was tapped to play alongside Ozzy at the closing ceremony for this year’s BlizzCon exhibition.

Gus G’s real name is Kostas Karamitroudis. He was born in Thessaloniki and grew up there before moving to the United States.

The performer has an endorsement deal with amplifier company Randall and has played in several heavy metal bands such as Mystic Prophecy, Nightrage, Arch Enemy and Dream Evil.

BlizzCon is a revered celebration for gamers, which celebrates the Warcraft, StarCraft and Diablo franchises as well as the communities that surround them.

The two day event was held at the Anaheim Convention Center in California, and included question and answer panels with Blizzard Entertainment developers, and many social events for players and developers to mingle