Activision offering upcoming band-specific spin-off to gamers who purchase next full installment of rockin' rhythm franchise.

There's an abundance of high-profile rhythm games headed for stores this holiday season, but Activision has an offer that could be music to the ears of cash-strapped gamers. The publisher today unveiled plans to give away its upcoming Van Halen-dedicated Guitar Hero spin-off with the purchase of Guitar Hero 5.

Activision's latest offer will help Guitar Hero and Van Halen fans save some cash.

While supplies last, specially marked copies of Guitar Hero 5 will include unique codes in their manual that can be redeemed for a copy of Guitar Hero: Van Halen either through the promotion's Web site or by mail. The offer ends October 31, and participants are asked to allow six weeks for delivery of the free game. That would put the title in a gamer's mailbox in mid-December at the latest, before the official December 22 retail debut of Guitar Hero: Van Halen.

The Web site for the promotion doesn't mention which retailers will carry the specially marked copies of Guitar Hero 5. However, it does link users directly to online retailer GameStop. [UPDATE] An Activision representative told GameSpot the "promotion will be valid at all retailers where the game is sold."

Guitar Hero 5 will feature 85 songs pulled from a number of genres, including Stevie Wonder's "Superstition," Megadeth's "Sweating Bullets," and Bob Dylan's "All Along the Watchtower." The title will also feature a number of in-game likenesses of artists, such as Johnny Cash, Santana, and Garbage singer Shirley Manson.

Like the Metallica- and Aerosmith-dedicated Guitar Hero games before it, Guitar Hero: Van Halen will feature 25 tracks from the hard rock group, as well as three playable solos by its famed guitarist, Eddie Van Halen. The game will also feature 19 other musical acts, including Queen, Weezer, Blink 182, The Offspring, and Queens of the Stone Age. Both titles will be available on the Xbox 360, PlayStation 3, Wii, and PlayStation 2.

For more on the games, check out GameSpot's previous coverage of Guitar Hero 5 and Guitar Hero: Van Halen.