Harmonix and MTV Games today announced four new tracks available for download in Rock Band Unplugged for the PSP. These four tracks join the 10 already released at launch via the Rock Band Unplugged in-game music store. The latest selection of songs span a variety of genres, including Metal, Alt Metal, Metalcore, and Prog Metal. Priced at just $1.99 per track, every head-banging, guitar-thrashing, parent-annoying RBU owner should grab these up as soon as possible either directly through the in-game store, or on the PSN through their PS3 or PC.

Tracks included in this latest pack are Avenged Sevenfold's "Afterlife", Dream Theater's "Constant Motion", Motley Crue's classic "Dr. Feelgood", and Stone Temple Pilot's hit "Sex Type Thing". Dokken fans will have to wait and see if their hair band gets included in a future release, sorry.

Rock Band Unplugged, based on the award-winning Rock Band series of games, features 41 songs on-disc that encompass popular tracks from the Rock Band music library, as well as nine songs exclusive to Rock Band Unplugged for a limited time before becoming available as downloadable content on other console versions. Staying true to the Rock Band franchise, the Rock Band Unplugged soundtrack spans all genres of rock, from punk and metal to alternative and classic rock, including Nirvana, Bon Jovi, The Police, Jackson 5 and Tenacious D.