Megadeth and Motörhead to shred axes on campus Thursday

This Thursday, two of the most popular popular metal bands will thrash the eardrums of eager fans at the Event Center.

Megadeth is on its seventh leg of Gigantour, their giant amalgamation of metal and heavy rock bands old and new. This also marks the first appearance of Giagantour ever in San Jose, and at lest Megadeth’s third — they visited the Event Center in 1995 and 1997.

This time around, Megadeth has recruited Motörhead, with its always-candid singer-songwriter-bassist Lemmy, to shred along 2012’s North American tour.

And yes, by this point, you’re wondering why you should care — metal, to you, is flat and one-dimensional. You see yourself at this week’s earlier “Big Time Rush” boy band quasi-opera.

Well, you’re wrong — metal is a complex beast and frequently evolving.

Arguably there are more than 45 distinct genres of metal, including fringe hybrids with punk and hardcore.

Samm Dunn, a metal music star and anthropologist, co-directed a film in 2005 entitled “Metal: a Headbanger’s Journey.”

Dunn describes metal as a culturally specific and frequently evolving genre. From Iran’s deathcore band, Death Fuse, to the Nintendocore group, Horse the Band, to Japan’s Mono, an instrumental post-metal band.

There is a huge global appeal to metal. And though you may haven’t heard the shrills from the guitar of an axe man from Norway, there is a great chance that people all across the globe are death metal devotees who will travel hundreds of miles for the opportunity to see their next favorite band.

Driven by a dark sound themed by macabre lyrics, religious symbols, dysfunctional relationships and holistic apathy, founded in hits such as Iron Butterfly’s 1968 release, “In-A-Gadda-Da-Vida,” and 1970’s Black Sabbath records “Black Sabbath” and “Paranoid.”

While hair bands began to boom in the early ‘80s, the earliest of the thrash bands begin to coalesce. The underground scene is where Dave Mustaine and Metallica founders James Hetfield and Lars Ulrich would meet. Mustaine was Metallica’s original lead guitarist, bringing along several songs, and arguably a certain joie de vivre from his previous bands.

Before Metallica recorded its pivotal album “Kill ‘Em All” in 1983, Mustaine co-wrote several Metallica songs, including fan favorite “The Four Horsemen” and the heavy hitter “Jump in the Fire.”

Mustaine, though, had a problem with drugs and alcohol and went his own way. Fired from Metallica, Mustaine went on to start another pivotal thrash metal band, Megadeth.

And like Metallica, Mustaine led his band by rocking the boat. And though epic solos and stacking arpeggios are found on tracks like 1992’s rock out, “Symphony of Destruction,” or the beautifully composed “Hangar 18” released in 1990, Megadeth had been driven by its conflicts.

The distinctive speed thrash metal that evolved out of the more than 20 band members that join and leave Megadeth over its first 20 years is driven by cocaine, heroin and alcohol, as well as the anger that these cause.

It produced a distinct, volatile sound fueled by substance abuse and clash.

The most famous beef involving Mustaine is his anger toward his former Metallica bandmates. One of his points: Metallica has won the Grammy Award for Best Metal Performance six times since the award was introduced 22 years ago. Megadeth, despite being nominated nine times, has not won.

It can be argued quite effectively that Mustaine didn’t play anywhere near his potential until he stopped playing.

In 2002, he triggered radial neuropathy, a form of cellular death, in his arm when having a kidney stone removed. At that point, Megadeth was disbanded. A pivotal metal band had finally met its end.

After a four-month recovery, he relearned how to play the guitar, arguably better, and learned to control himself. Post-Born-Again Christian, he had a new Megadeth that didn’t tour with satanic bands and had a more “positive” message.

Three years later, he, with new band members, released “The System has Failed.” It was different than the metal he had played before, and, though not all the original fans were happy with its more technical sound, it solidified this new Megadeth as a part of the major American metal landscape.

That same year, Mustaine set off the inaugural Gigantour, featuring thrash metal co-founders Anthrax as well as mathcore’s best and scariest, Dillinger Escape Plan, progressive metal godfathers Dream Theater, and a slue of equally fantastic metal bands.

Mustaine has since become a quasi-political and cultural figure, announcing that, as a part of his alcoholics anonymous process and whatever other excuse he chooses to give, he is now a born-again Christian, disavows gay marriage, thinks President Obama is a divisive politician and believes that Rick Santorum would make a great new president. (But does not formally endorse him.) I’m not sure why it seems so many metal bands, especially the most macabre, end up becoming extremely religious and conservative. (See: Korn or Insane Clown Posse.)

The annual global tour has featured many sold-out dates and produced several CD’s and DVD’s of Gigantour live performances. I argue each year’s iteration since has not had as potent of a lineup, but this is the closest it’s gotten.

Motörhead will provide a colorful gritty set as co-headliner, and Danish rock band Volbeat and nu-metal group Lacuna Coil will provide support as opening acts.

If you find yourself in need of a headbanging moment or desire to thrash around in a metal pit, tickets are still available for $39.50.

It will be loud, and you will go deaf. Rock on. This Thursday, Megadeth and Motörhead will rock the Event Center.