Metallica's Australian tour is shaping up as some kind of monster.

Four arena concerts have been added to the Australian leg of Metallica's World Magnet Tour in a response to "overwhelming demand" for tickets, promoter Michael Coppel Presents announced today (May 11).

The metal veterans' Australian run has doubled in size to 12 dates; when Melbourne-based MCP unveiled the tour last month, just six shows were on the slate.

The tour, Metallica's first on these shores since 2004, will kick off Oct. 18 with successive nights at the Brisbane Entertainment Centre, followed by two dates at Burswood Dome in Perth, a hat-trick of performances at Sydney's Acer Arena, a pair of shows at Adelaide's Entertainment Centre and concludes Nov. 21 with the last of three shows at Melbourne's Rod Laver Arena.

Although the latest trek stretches across more than a full month, the band members won't be sunning themselves in Australia for the duration. There is a two-week gap in the middle of the itinerary, which allows the group to return home to San Francisco for a break.